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40 [Latest] Bitcoin Job Interview Questions and Answers PDF


Real Time Bitcoin Interview Questions and Answers PDF


•    What Is Bitcoin Mining?
Bitcoin mining is analogous to the mining of gold, but its digital form. The process involves specialized computers solving algorithmic equations or hash functions. These problems help miners to confirm blocks of transactions held within the network. Bitcoin mining provides a reward for miners by paying out in Bitcoin in turn the miners confirm transactions on the blockchain. Miners introduce new Bitcoin into the network and also secure the system with transaction confirmation. They are also rewarded network fees for when they harvest new coin and a time when the last bitcoin is found mining will continue.

•    Why Bother With Bitcoin?
That’s the million Dollar question, and there’s probably a ton of answers you could give yourself. Are you fascinated by money and technology? Do you want to push the boundaries of money itself and participate in one of the biggest economic experiments of the past century?
At some point you’ll hear people say “Bitcoin is great, but you’ll never use it to buy your coffee every morning”. It’s a sign they haven’t really sat down to think about what money is, or how different people around the world use it. In fact, people are already using Bitcoin to buy their morning coffee!
Are you unserved or underserved by the current international banking system because you or your family live in an emerging economy, or freelance for clients overseas? Are you under 18, or work in an industry the credit card companies or PayPal don’t approve of? Have you ever had an account frozen for some random irregularity, or had to pay over $20 in international money transfer fees just to send your funds to a friend or loved one? Bitcoin is the perfect solution to all of those issues.
If you’re a merchant – either online or brick-and-mortar – accepting Bitcoin is faster and cheaper than credit cards, and all payments are final. Fees are lower and there’s no risk of fraudulent chargebacks.
Perhaps you think the value of Bitcoin will increase in future and want to invest in it. Or maybe you’ve been reading about the existing fiat currency/central banking and international financial system, realize something’s not quite right with it and want to place control of your money back in your own hands. Bitcoin allows you to do this.
Hirred Bitcoin Interview Questions And Answers

•    How Is The Blockchain Different From Banking Ledgers?
Banks and accounting systems use ledgers to track and timestamp transactions. The difference is that the blockchain is completely decentralized and open source. This means that people do not have to rely on or trust the central bank to keep track of the transactions. The peer-to-peer blockchain technology can keep track of all the transactions without the fear of having them erased or lost.
Furthermore, the blockchain, because of its open source nature, is more versatile and programmable than central banking ledgers. If programmers need new functionality on the blockchain, they can simply innovate on top of already existing software through consensus. This is difficult for central banks because of all of their regulations and central points of failure.

•    How Can You Buy Bitcoin?
Bitcoins can be bought from various sources. You can purchase them online using an exchange or brokerage service that will enable you to buy Bitcoin with a bank transfer using fiat currency, a credit card, and some services also offer buying opportunities using Paypal. Bitcoin can also be purchased locally using LocalBitcoins, and from Bitcoin Teller Machines which are similar to cash ATMs that you find worldwide.
Bitcoin.com offers a recommended list of current online exchanges and brokers who sell bitcoins. You can also buy Bitcoins instantly using your credit card on Bitcoin.com (The service is provided by Simplex). Our aim is to provide the best quality services via our website so anyone can easily obtain the cryptocurrency from a wide array of respected Bitcoin buying/selling platforms.

•    What Is Double Spending?
Double-Spending is the act of using the same bitcoins twice. There is only a 21 million set cap on the protocol and no more can be produced. So the network protects against double spend by the verification of each recorded transaction. The blockchains ledger ensures that the transactions are finalized by its inputs confirmed by miners. The confirmations make each unique Bitcoin and its subsequent transactions legitimate. If one tried to duplicate a transaction the original blocks deterministic functions would change showing the network that it is counterfeit and would not to be accepted.

•    What Is The Blockchain?
Bitcoin is dependent on the blockchain that underlies and structures the system. The blockchain is the vertebrae of the protocol and the glue that holds the network together. It is simply a vast, distributed public ledger of account. It keeps track of every transaction ever made in the network, and all transactions are timestamped and verified by network miners. This is how it works: miners with specialized computers compete to solve mathematical puzzles with other computers, and once they solve a puzzle they are awarded with some Bitcoin, but they also add a “block” of completed transactions to the blockchain for future viewing and verifiability.
Once a block is added to the chain the cycle repeats itself, and the computers continue to compete to solve these difficult problems. Every transaction on the blockchain is completely transparent and accounted for in its log. Anyone can see the public keys of any transaction they want (although there are no names associated with transactions). One could go all the way back and view the very first transactions ever made on the first block ever created. This block was unironically called the Genesis Block.

•    Who Developed Bitcoin?
The original Bitcoin code was designed by Satoshi Nakamoto under MIT open source credentials. In 2008 Nakamoto outlined the idea behind Bitcoin in his White Paper, which scientifically described how the cryptocurrency would function. Bitcoin is the first successful digital currency designed with trust in cryptography over central authorities. Satoshi left the Bitcoin code in the hands of developers and the community in 2010. Thus far hundreds of developers have added to the core code throughout the years.

•    What Is It And Why Is It Important?
Bitcoin‘s inventor, Satoshi Nakamoto, described Bitcoin as “A Peer-to-Peer Electronic Cash System” in the original 2009 Bitcoin whitepaper – the document which created the roadmap for Bitcoin. To date, this is still the most simple and accurate description.
Bitcoin is a consensus network that enables a new payment system and a completely digital money. It is the first decentralized peer-to-peer payment network that is powered by its users with no central authority or middlemen. From a user perspective, Bitcoin is perhaps best described as ‘cash for the Internet’, but Bitcoin can also be seen as the most prominent triple entry bookkeeping system in existence.
It is also known as digital cash, cryptocurrency, an international payment network, the internet of money – but whatever you call it, Bitcoin is a revolution that is changing the way everyone sees and uses money.
The beauty of Bitcoin is that it requires no central servers or third-party clearing houses to settle transactions – all payments are peer-to-peer (P2P) and are settled in about 10 minutes – unlike credit card payments, which can take weeks or months before they’re finally settled.
All Bitcoin transactions are recorded permanently on a distributed ledger called the “blockchain” – this ledger is shared between all full Bitcoin “miners” and “nodes” around the world, and is publicly-viewable. These miners and nodes verify transactions and keep the network secure. For the electricity they use to do this, miners are rewarded with new bitcoins with each 10-minute block (the reward is currently 12.5 BTC per block).
The Bitcoin protocol is also hard-limited to 21 million bitcoins, meaning that no more than that can ever be created. This means that no central bank, individual or government can come along and simply ‘print’ more bitcoins when it suits them. In this sense Bitcoin is a deflationary currency, and as such is likely to grow in value based on this property alone.
Bitcoin is still a cutting-edge experiment in technology and economics, and like the worldwide web in 1995, its myriad potential, purposes and applications are yet to be decided. Is it just electronic money? A foundation for smart contracts and electronic shares? Is it underground and subversive, challenging the power of governments, or will it integrate into mainstream finance and go unnoticed? If you know the answers to any of these questions, or if you can figure out how to capitalize on them there may be many lucrative opportunities for you in the Bitcoin space.
The Bitcoin universe is changing fast and often – to stay ahead of the game it’s necessary to follow the news almost-hourly and discuss the latest events with other members of the community. Bitcoin.com exists to be a reliable information hub for beginners and industry insiders alike. That being said, ‘staying ahead of the game’ is not a necessity if you simply wish to use Bitcoin as a currency to purchase goods and services, or wish to accept Bitcoin for transactions – something thousands of people around the world do every single day.

•    Can You Sell Bitcoin?
Bitcoins can be sold in various fashions. The currency can be sold online to an exchange or live in person locally. These same instances work similarly to the buying process. You can sell your Bitcoin to the exchange at the current price it's being sold for. More anonymously you can sell in person or use a localized 2-way ATM. ATMs can be found all over the world and these machines are mostly used for purchasing. 2-way ATMs can allow you to sell the currency. Most ATMs however only allow you to buy Bitcoin. There are also teller machines that require identification as well.
Bitcoin payments are easy to make with a wallet application and addresses. You can use a standard desktop or smartphone to transact with an individual, merchant and exchange. Addresses can be used in number form, in a QR code and contactless technology. Transacting with Bitcoin offers lower fees than any known remittance provider and credit card service. No bank, no state, no third party can offer this low amount of fees.

•    Can Stores Accept Bitcoin?
Brick and mortar outlets can also accept Bitcoin. Services like Coinbase, CoinKite, and BitPay offer applications and hardware for the convenience of the store owner. Most of these businesses offer invoicing and accounting with their services. However, third party services are not required by physical merchants to accept the currency. Individual users can also accept Bitcoin directly and handle the transactions and accounting themselves. Bitcoins can be sold in various fashions. The currency can be sold online to an exchange or live in person locally.
These same instances work similarly to the buying process. You can sell your Bitcoin to the exchange at the current price it's being sold for. More anonymously you can sell in person or use a localized 2-way ATM. ATMs can be found all over the world and these machines are mostly used for purchasing. 2-way ATMs can allow you to sell the currency. Most ATMs however only allow you to buy Bitcoin. There are also teller machines that require identification as well.
Bitcoin payments are easy to make with a wallet application and addresses. You can use a standard desktop or smartphone to transact with an individual, merchant and exchange. Addresses can be used in number form, in a QR code and contactless technology. Transacting with Bitcoin offers lower fees than any known remittance provider and credit card service. No bank, no state, no third party can offer this low amount of fees.

•    Why Trust Bitcoin?
Bitcoin is a network operating by the three foundational principles of technological freedom: Decentralization, Open Source code, and true Peer-to-Peer technology. Bitcoin’s trust is based on the subjective valuations of human faith in mathematical algorithms, encryption and numbers. With the three pillars of technological principles Bitcoin’s blockchain is a peer-reviewed system of integrity.

•    Is Bitcoin Anonymous?
Participants in Bitcoin transactions are identified by public addresses – those are the long strings of around 30 characters you see in a person’s Bitcoin address, usually starting with the numerals ‘1’ or ‘3’. For every transaction, the sending and receiving addresses are publicly-viewable.
Since these numbers are virtually incomprehensible, difficult to remember without a computer and don’t contain a person’s name or identifying information, it is often claimed that Bitcoin is an “anonymous currency”. This is also often used as an argument to attack Bitcoin as a currency for illegal transactions and tax evasion.
But it’s not as simple as that. If you publish your address anywhere, it can be linked to your real-life identity. Even if you don’t publish it, simply re-using the same address many times can show a pattern that an analyst with basic skills could link to your identity by looking at transaction times, amounts, location and regularity – and connecting it to other data sources like receipts, exchanges, and shipped items.
It’s recommended for privacy and security that you use a new address for every single transaction, and most modern wallet software is designed to do just that. But even though this increases the amount of effort and skill required to uncover your identity, it doesn’t make you 100% anonymous. Freely available blockchain explorers and analytical tools have been used to link addresses with only single transactions to other addresses, forming a chain or pattern that eventually reveals its owner. These have been useful in investigating cases of theft at companies like Mt. Gox and Bitcoinica, but can potentially be used to identify anyone.
Due to all of this, it’s more accurate to say Bitcoin is “pseudonymous” and not anonymous. Think of it as a less memorable email address or online handle. Even if it’s not your real name, someone out there can potentially find out who the real person behind the pseudonym is.

•    What Can Bitcoin Do?
The Bitcoin protocol can change the financial landscape we see today. The protocol can act as a currency, voting mechanism, global identification and reputation application, a micro-tipper, crowdfunding platform, initiate trusts, wills and contracts, decentralized domain names, future markets, and basically everything the financial system of today can handle plus so much more. The currency application is just the beginning of this evolution of world's finances.

•    What Happens If I Lose My Bitcoins?
Unfortunately, since unique private keys are associated with individual Bitcoin wallets, if the keys are lost, there is ultimately no way to retrieve that key without a passcode seed or other retrieval system; and that key is required to spend those coins. However, most modern wallets, like Mycelium, have wallet and key backups that you can build prior to storing money. This will allow you to create a new private key so that you may restore your private key on a new wallet if lost.

•    Who Is In Charge Of Bitcoin?
Nobody is "in charge" of Bitcoin – at least in the sense that Bitcoin is not a company or organization, has no governing body and no organizational structure. Bitcoin is simply a software protocol, like HTTP (aka the Internet and SMTP (aka email).
This has been the case since Bitcoin’s creator, the person (or persons) calling themselves Satoshi Nakamoto, released their creation into the wild in 2009. There are, however, certain groups who can exert influence over the way Bitcoin functions through various means.
Again, though, there are no individuals who can claim to speak for these groups and they contain a plethora of opinions and incentives within. Examples of such groups are: Developers: These are the people who write and maintain the software the Bitcoin network runs on. Although Satoshi Nakamoto released the first version of Bitcoin himself in 2009, the code has since been re-written and updated by subsequent programmers.
The developers choose what updates to make to the protocol, and consider ways it can be improved. Miners: These are the people (and companies) that own the machines that generate new bitcoins and keep the network secure by validating transactions. As a result, they have the power to "vote" with their hardware and choose which Bitcoin software to support.
Developers may create and release radical revisions to the Bitcoin protocol, but they'll have no effect unless the Bitcoin miners choose to adopt them. Users: That's you. At the end of the day, if regular users decide Bitcoin no longer fulfils their needs, then it will have no value. You can see the user effect in action just by looking at alternative cryptocurrencies collectively known as ‘altcoins' – there are currently about 700 different altcoins of varying degrees of popularity. They have risen and fallen in favor as users decided whether to buy, hold, sell, or simply abandon.
Merchants have made individual decisions as to whether to accept them as payment or not. Bitcoin faces the same market conditions, and there's no shortage of new projects claiming their protocol is superior. So far none have knocked Bitcoin from its position as the most popular cryptocurrency, but there's no guarantee this will always be the case. Large holders, venture capitalists and influential figures in the "Bitcoin community" could also affect Bitcoin's future path, though their influence is less direct. And again, there is rarely a consensus of vision among them.

•    What Is A Bitcoin Wallet?
Like the name suggests, a Bitcoin wallet is an application that stores, sends and receives bitcoins. You can think of it like you would a leather wallet full of physical cash, and basically that’s all you need to use Bitcoin.
The most common wallets are smartphone-based, and use the device’s camera to scan QR codes to save the user from needing to copy/paste long Bitcoin addresses. Other people have desktop versions or use browser-based wallets. To the end user the interface is similar, though the way they function and handle private keys (the ‘key’ which allow you to spend your bitcoins) and user privacy can be very different.
Some apps have features that add value to your Bitcoin-using experience, like location-based Bitcoin business guides, links to exchanges to trade in and out of fiat currencies, more secure vault storage, or the ability to hold digital tokens other than just Bitcoin, such as any number of the many altcoins on offer.
Some wallets have central servers, meaning users have to create accounts with a login name (usually an email address) and password. These are less private and (if login info and keys are not secured properly) may be vulnerable to hackers. On the upside, when a centralized wallet is used if a user forgets their password it’s usually recoverable.
Other wallets store all information and private keys on the device itself, some of which generate wallet keys from a single “seed” phrase of about 12 words. If a user remembers the seed phrase, then the wallet can be restored elsewhere if the device is lost or broken. On the downside, if you forget that seed phrase the wallet can’t be recovered.
Apart from smartphone/desktop apps you can also buy specialized hardware devices like Trezor and Ledger to keep your keys completely offline, or even print a wallet on paper to keep them as safe from hackers as possible. These are the best options for users holding large amounts of Bitcoin.
Bitcoin users now have a wide selection of wallets to choose from and features have improved vastly over the past couple of years. But with more choice comes the need for more caution: fraudulent Bitcoin wallets have begun to appear that mimic the look of popular wallets, but are actually malware that steals bitcoins.

•    Why Does The Bitcoin Price Move So Much?
Until Bitcoin becomes the dominant currency for payments around the world, it will be more popular among traders and price speculators. As a result, the price is subject to the market forces of supply and demand which, at this point in time, goes hand in hand with the trends and whims of speculators – as a result, the price can move suddenly and sharply up or down in response to news events.
As a rule of thumb: if a piece of news makes Bitcoin more likely to be widely adopted, the price rises. If it places extra hurdles towards mass adoption, the price will fall.
You can track all the latest Bitcoin price movements in real time with Bitcoin.com’s data charts, and convert the price to your local currency with our instant Price Converter.
These events may be based on issues affecting the Bitcoin world only – such as a large scale hack affecting a key Bitcoin exchange, wallet or essential software which causes the price to dip. This happened after the Mt. Gox meltdown in 2014 and thefts at Bitstamp and Bitfinex, plus numerous other smaller companies.
A large market such as the EU, China, Japan or US may announce new regulations either favorable or restrictive to Bitcoin, causing the price to rise or fall respectively (when the Chinese government restricted Bitcoin exchanges’ practices in 2013, the price fell from its record high). It may be an internal issue, such as a miners’ conference or meeting to decide changes to the Bitcoin protocol; the price sometimes dips if a block size or scaling consensus cannot be reached, or seems to be too far off.
News which affects the price may be only vaguely related to Bitcoin, or sometimes not at all. Dramatic economic/financial news like new tax policies, bank runs or bailouts, negative interest rates, stock market crashes, banking instability or government bankruptcies all suggest a new kind of asset class may be preferable, and the Bitcoin price rises.
The price sometimes fluctuates wildly for no apparent reason at all. Sudden crashes, massive increases and up/down volatility can happen and, even after the fact, traders debate over what may have caused it. A large price build-up may suddenly reverse when it hits a certain price level, at which point traders set limit orders and/or take profits. The inverse happens if the price drops too far.
Some have suggested Bitcoin can never be adopted as a regular currency while prices are so volatile. In truth, if there was a sudden rush to Bitcoin among the general public (maybe due to a crisis in a major fiat currency) the price would probably rise dramatically and then stabilize – especially if there was nothing to swap it for, or no reason to do so.
In the meantime, if you think you can predict the big movements then good luck on the trading exchanges! But be careful, it can also be inexplicable and unpredictable.

•    How Can I Trade Bitcoin Without An Exchange?
There are plenty of reasons to want to trade Bitcoin for fiat and other digital tokens without an exchange.
The main one is security and trust – two of the largest Bitcoin exchanges of all time, Mt. Gox and Bitfinex, have suffered catastrophic hacks in the past and lost hundreds of thousands of their users’ BTC. Not to mention the multiple other smaller exchanges that were hacked or disappeared in mysterious circumstances.
Another is privacy – exchanges these days have similar know-your-customer (KYC) requirements to banks. All this information is kept on file and, like your funds, is at risk of theft if the exchange’s security isn’t up to scratch.
Person-to-person trading is a small but growing market, with services like LocalBitcoins facilitating individual trade deals between users. Some also use online classifieds like Craigslist or even chat groups on apps like Telegram and WeChat to indicate willingness to trade in person. Other services like BitKan have special apps designed to introduce you to online buyers who may not be in your physical location.
Be aware that, in many jurisdictions, even trading with other individuals in a private arrangement is regulated by KYC and anti money laundering (AML) laws, meaning you could be at risk if you don’t know anything about the people you’re trading with. As such, it is important to clarify your local laws before engaging in person to person trades.

•    Can I Make Money Mining Bitcoin?
The days where anyone could make money mining Bitcoin with a desktop computer or GPU cards are unfortunately long gone. The total computing (or “hashing”) power of the network has risen exponentially since the introduction of application-specific integrated circuits (ASICs), or machines designed specifically to solve Bitcoin’s mining proof-of-work algorithm and nothing else.
It is still possible for individual miners to make some money by purchasing their own ASIC-based equipment – however, most mining takes place in large factory-like environments with hundreds of machines, in places where energy is cheap (such as China and above the Arctic Circle). And once your machine is superseded by a newer model a few months after purchase, its ability to compete on the network (and thus its earning potential) is greatly diminished, along with its resale value.
You also need to consider energy costs where you live. Bitcoin-mining ASIC machines run very hot and consume large amounts of electricity. You’ll need to subtract the costs of electricity and cooling from the profits you make.

•    How Can I Sell Bitcoins?
Bitcoins can be sold locally using LocalBitcoins, on Bitcoin brokerages / exchanges, using two-way Bitcoin Teller Machines (BTM’s) or you can pay for a good or service with them. Bitcoins can be sold to just about anyone as long as they have a Bitcoin address, and can be sold for any fiat currency in the world or traded for a physical good. Feel free to check out our recommended list of exchanges and brokerage services to sell your bitcoins online.

•    What Can You Buy With Bitcoin?
You can purchase just about anything with bitcoins, from goods like clothing, electronics, food and art to handmade crafts. Bitcoin can also be used to purchase large items like cars, real estate, and investment vehicles such as precious metals. By using Purse.io users can buy just about anything from Amazon and get a discount of up to 20% just by using Bitcoin. Additionally, many merchants who accept Bitcoin also give discounts for people who pay with the digital currency. Show your friends how easy it is to use bitcoin – head over to our own bitcoin.com Store and buy a T-shirt, hoodie, bag, all kinds of accessories, even art and bitcoin wallet hardware.
Bitcoin.com offers a searchable database that enables our users to search for specific items sold for Bitcoin. Just type in the product you wish to purchase using Bitcoin and you’ll see a list of online merchants selling that item. For merchants that don't accept Bitcoin, there's still a way to use your cryptocurrency to purchase the items you’re interested in by using a Bitcoin debit card. Bitcoin.com has a list of Bitcoin debit card companies to choose from; some cards can only be issued to certain countries, and all have varying fees so be sure to read up on your options in order to choose the best card for you.
For cryptocurrency enthusiasts, Bitcoin.com also has its own store which sells Bitcoin-related merchandise such as T-shirts, artwork, coffee mugs, Bitcoin famous Alpaca socks and more. If you're looking for some Bitcoin swag make sure you head over to our store to find quality items that make great conversation pieces and show off the Bitcoin spirit.

•    What Is A Bitcoin Address?
A Bitcoin address is a long string of 27 - 34 numbers and letters that acts similarly to an email address. The address enables the Bitcoin blockchain to recognize when bitcoins are sent and received. These addresses can be used by anybody, from single individuals to businesses to multiple people accessing the one address if desired. It is also considered more secure not to re-use addresses but rather to use a unique address every time you send and receive bitcoins. This increases the privacy of your transactions to a degree and helps in avoiding public tracking of your funds.

•    How Do Bitcoin Transactions Work?
Bitcoin transactions are composed of an amount, an input (sending address), an output (receiving address) and private keys (the keys which allow you to spend your bitcoins). A user simply enters a receiving address and if the person possesses the private key associated with the bitcoins they are trying to spend the transaction is sent and verified with the help of miners confirming blocks of exchanges (transactions) within the Bitcoin blockchain. The blockchain is a database of all recorded transactions since Bitcoin’s inception.

•    What Is A Public Key?
Every Bitcoin address contains both a public and a private key. The public key allows others to send bitcoins to your address, and verifies the signature of the transaction to ensure everything is in order and finalizes the transaction. The private key, on the other hand, allows you to ‘unlock’ and spend your bitcoins. It does this by signing transactions, which tells the Bitcoin network that you are indeed the owner of the address in which the bitcoins are held and that the transaction is valid.
Whoever holds the private key for a Bitcoin address is able to spend the bitcoins which that address holds, so in a very fitting analogy your private key is essentially the key to the safe which is holding your bitcoins. You can also use the private key of an address to sign a message, verifying that you are the owner of the bitcoins held at any given address. This is all secured through mathematics, using asymmetric cryptography.

•    How To Accept Bitcoin Payments For Your Store?
It is very easy for any merchant to accept Bitcoin, and most of the time preparing to add the feature to your payment services takes less than 10 minutes. Merchants can accept Bitcoin both online and at physical locations by using a merchant service payment provider like Bitpay, or even just using a simple wallet address generated on their own device. Bitcoin has significantly lower fees than PayPal, credit card companies and bank services making it far more appealing to store owners than the legacy payment card processors.
The cryptocurrency is also irreversible so chargebacks are not possible, and this leaves the decision to refund fully within the hands of the store owner. Merchants can accept Bitcoin through a payment processor, through a Point-Of-Sale (POS) device or simply using their own tablet or smartphone. Adding Bitcoin as a payment method for your store can also increase your customer base for those who like to pay with cryptocurrency as well as broadening your company’s reach into the global market.

•    What Are The Fees Involved?
There are fees involved with sending Bitcoin called the ‘Miner’s fee.’ Fees are paid to the miners in order for them to verify and secure Bitcoin transactions within the network. A website / developer’s solution named ‘21’ offers an online guide detailing the fees within the network for certain time frames. Typically, a larger fee will confirm faster than a relatively low one.

•    What Does "unconfirmed Transaction" Mean?
An unconfirmed transaction is a transaction in the network that the miners have yet to confirm. Typically, confirmations take roughly 10 minutes. However due to the increased popularity of the Bitcoin network confirmation times have increased quite a bit and can sometimes take op to an hour or more. There are solutions in the works to deal with this issue, as well as a lot of discussion within the Bitcoin community around the best way to go about it. If a transaction fails to confirm after 72 hours, the funds will be sent back to the original sender’s wallet.

•    Is Bitcoin Legal?
Bitcoin is legal in most jurisdictions in the world but there are a small number nation states that have banned its use, such as Ecuador. Wikipedia has a great guide on how Bitcoin is treated in all the countries around the world and explains regulatory policies surrounding it. Regulations vary from one border to the next so you should always research your location’s laws before participating in the network.

•    Who Is Satoshi Nakamoto?
Satoshi Nakamoto is a pseudonym/name of a person or group of people who created the original Bitcoin client and author of the original reference white paper which details the protocol. Nakamoto participated in the network by helping with the code and mining until 2010 when he/they disappeared, never to be heard from again.

•    How To Make A Bitcoin Paper Wallet?
Paper wallets are a great way to keep Bitcoin offline and out of hacker's reach. Creating paper wallets is easy but losing the paper also means the bitcoins are lost forever so be careful. Paper wallets contain both private and public keys which allow you to spend your bitcoins. The most common way that people creates paper wallets is a website, BitAddress.org, where users can generate a fresh new Bitcoin address and related private key. The website will ask the person to initiate some steps and are then given both public and private keys after the process.
From there all one has to do is print the paper wallet using BitAddress.org’s website or another service. After printing a copy, you can load as much bitcoin as you want into your public QR-code. This service, however, does come with a caveat. There are any number of technical reasons why generating a private key on a machine that you don’t control is a bad idea; these range from man-in-the-middle (MITM) attacks to untrustworthy site operators, and everything in between. However, downloading the Bitaddress code and running it on your own machine offline can mitigate these risks. This can be further secured by doing so on a machine that is not (and has never been) connected to the internet.

•    How Does The Blockchain Work?
The blockchain records all of the newly minted bitcoins rewarded to miners who find blocks. Blocks are sets of sent/received transactions that miners confirm for the network. As these actions take place within the Bitcoin protocol the blockchain acts as a ledger of account for all transactions undertaken within the Bitcoin network.

•    What Is A Full Node?
Bitcoin transactions need more than just miners to validate and relay across the network. Full nodes are maintained by individuals, groups and organisations all around the world and broadcast all the messages within the protocol. Full nodes are a second layer of security for the Bitcoin network and operate in an altruistic manner meaning they work without reward. The use of full nodes increases the networks vitality and reduces double spending immensely.

•    Who Created Bitcoin?
Bitcoin is the first implementation of a concept called "crypto-currency", which was first described in 1998 by Wei Dai on the cypherpunks mailing list, suggesting the idea of a new form of money that uses cryptography to control its creation and transactions, rather than a central authority. The first Bitcoin specification and proof of concept was published in 2009 in a cryptography mailing list by Satoshi Nakamoto. Satoshi left the project in late 2010 without revealing much about himself. The community has since grown exponentially with many developers working on Bitcoin.
Satoshi's anonymity often raised unjustified concerns, many of which are linked to misunderstanding of the open-source nature of Bitcoin. The Bitcoin protocol and software are published openly and any developer around the world can review the code or make their own modified version of the Bitcoin software. Just like current developers, Satoshi's influence was limited to the changes he made being adopted by others and therefore he did not control Bitcoin. As such, the identity of Bitcoin's inventor is probably as relevant today as the identity of the person who invented paper.

•    Who Controls The Bitcoin Network?
Nobody owns the Bitcoin network much like no one owns the technology behind email. Bitcoin is controlled by all Bitcoin users around the world. While developers are improving the software, they can't force a change in the Bitcoin protocol because all users are free to choose what software and version they use. In order to stay compatible with each other, all users need to use software complying with the same rules. Bitcoin can only work correctly with a complete consensus among all users. Therefore, all users and developers have a strong incentive to protect this consensus.

•    How Does Bitcoin Work?
From a user perspective, Bitcoin is nothing more than a mobile app or computer program that provides a personal Bitcoin wallet and allows a user to send and receive bitcoins with them. This is how Bitcoin works for most users.
Behind the scenes, the Bitcoin network is sharing a public ledger called the "block chain". This ledger contains every transaction ever processed, allowing a user's computer to verify the validity of each transaction. The authenticity of each transaction is protected by digital signatures corresponding to the sending addresses, allowing all users to have full control over sending bitcoins from their own Bitcoin addresses. In addition, anyone can process transactions using the computing power of specialized hardware and earn a reward in bitcoins for this service. This is often called "mining". To learn more about Bitcoin, you can consult the original whitepaper.

•    Is Bitcoin Really Used By People?
Yes. There is a growing number of businesses and individuals using Bitcoin. This includes brick and mortar businesses like restaurants, apartments, law firms, and popular online services such as Microsoft, Dell, and Newegg. While Bitcoin remains a relatively new phenomenon, it is growing fast. At the end of March 2016, the value of all bitcoins in circulation exceeded US$ 6.5 billion with millions of dollars worth of bitcoins exchanged daily.

•    How Does One Acquire Bitcoins?
o    As payment for goods or services.
o    Purchase bitcoins at a Bitcoin exchange.
o    Exchange bitcoins with someone near you.
o    Earn bitcoins through competitive bitcoin mining.
While it may be possible to find individuals who wish to sell bitcoins in exchange for a credit card or PayPal payment, most exchanges do not allow funding via these payment methods. This is due to cases where someone buys bitcoins with PayPal, and then reverses their half of the transaction. This is commonly referred to as a chargeback.

•    How Difficult Is It To Make A Bitcoin Payment?
Bitcoin payments are easier to make than debit or credit card purchases, and can be received without a merchant account. Payments are made from a wallet application, either on your computer or smartphone, by entering the recipient's address, the payment amount, and pressing send. To make it easier to enter a recipient's address, many wallets can obtain the address by scanning a QR code or touching two phones together with NFC technology.

•    What Are The Advantages Of Bitcoin?
o    Payment freedom: It is possible to send and receive any amount of money instantly anywhere in the world at any time. No bank holidays. No borders. No imposed limits. Bitcoin allows its users to be in full control of their money.
o    Very low fees: Bitcoin payments are currently processed with either no fees or extremely small fees. Users may include fees with transactions to receive priority processing, which results in faster confirmation of transactions by the network. Additionally, merchant processors exist to assist merchants in processing transactions, converting bitcoins to fiat currency and depositing funds directly into merchants' bank accounts daily. As these services are based on Bitcoin, they can be offered for much lower fees than with PayPal or credit card networks.
o    Fewer risks for merchants: Bitcoin transactions are secure, irreversible, and do not contain customers’ sensitive or personal information. This protects merchants from losses caused by fraud or fraudulent chargebacks, and there is no need for PCI compliance. Merchants can easily expand to new markets where either credit cards are not available or fraud rates are unacceptably high. The net results are lower fees, larger markets, and fewer administrative costs.
o    Security and control: Bitcoin users are in full control of their transactions; it is impossible for merchants to force unwanted or unnoticed charges as can happen with other payment methods. Bitcoin payments can be made without personal information tied to the transaction. This offers strong protection against identity theft. Bitcoin users can also protect their money with backup and encryption.
o    Transparent and neutral: All information concerning the Bitcoin money supply itself is readily available on the block chain for anybody to verify and use in real-time. No individual or organization can control or manipulate the Bitcoin protocol because it is cryptographically secure. This allows the core of Bitcoin to be trusted for being completely neutral, transparent and predictable.

•    What Are The Disadvantages Of Bitcoin?
o    Degree of acceptance: Many people are still unaware of Bitcoin. Every day, more businesses accept bitcoins because they want the advantages of doing so, but the list remains small and still needs to grow in order to benefit from network effects.
o    Volatility: The total value of bitcoins in circulation and the number of businesses using Bitcoin are still very small compared to what they could be. Therefore, relatively small events, trades, or business activities can significantly affect the price. In theory, this volatility will decrease as Bitcoin markets, the technology matures and Bitcoin interest rates normalize. Never before has the world seen a start-up currency, so it is truly difficult (and exciting) to imagine how it will play out.
o    Ongoing development: Bitcoin software is still in beta with many incomplete features in active development. New tools, features, and services are being developed to make Bitcoin more secure and accessible to the masses. Some of these are still not ready for everyone. Most Bitcoin businesses are new and still offer no insurance. In general, Bitcoin is still in the process of maturing.

•    Why Do People Trust Bitcoin?
Much of the trust in Bitcoin comes from the fact that it requires no trust at all. Bitcoin is fully open-source and decentralized. This means that anyone has access to the entire source code at any time. Any developer in the world can therefore verify exactly how Bitcoin works. All transactions and bitcoins issued into existence can be transparently consulted in real-time by anyone. All payments can be made without reliance on a third party and the whole system is protected by heavily peer-reviewed cryptographic algorithms like those used for online banking. No organization or individual can control Bitcoin, and the network remains secure even if not all of its users can be trusted.

•    Is Bitcoin Fully Virtual And Immaterial?
Bitcoin is as virtual as the credit cards and online banking networks people use everyday. Bitcoin can be used to pay online and in physical stores just like any other form of money. Bitcoins can also be exchanged in physical form such as the Open Dime, but paying with a mobile phone usually remains more convenient. Bitcoin balances are stored in a large distributed network, and they cannot be fraudulently altered by anybody. In other words, Bitcoin users have exclusive control over their funds and bitcoins cannot vanish just because they are virtual.

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