Bitcoin is a virtual currency that gained recognition after its price-per-coin rose above $13,000 in early 2018. The cryptocurrency (one of many) is at the center of a complex intersection of privacy, banking regulations, and technological innovation. Today, some retailers accept bitcoin, while in other jurisdictions, bitcoin is illegal.

Cryptocurrency Defined

Cryptocurrencies are lines of computer code that hold monetary value. These lines of code are created by electricity and high-performance computers.

Cryptocurrency is also known as digital currency. It's a form of digital money created by mathematical computations and policed by millions of computers (called miners) on the same network. Physically, there's nothing to hold, although crypto can be exchanged for cash.

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Crypto comes from the word cryptography, which is the process used to protect the transactions that send the lines of code for purchases. Cryptography also controls the creation of new coins. Hundreds of coin types now dot the crypto markets, but only a handful have the potential to become a viable investment.

Governments have no control over the creation of cryptocurrencies, which is what initially made them so popular. Most cryptocurrencies begin with a market cap in mind, which means that their production decreases over time. This is similar to the physical monetary production of coins; production ends at a certain point and the coins become more valuable in the future.

What Are Bitcoins?

Bitcoin was the first popular cryptocurrency. No one knows who created it — most cryptocurrencies are designed for maximum anonymity — but bitcoins first appeared in 2009 from a developer reportedly named Satoshi Nakamoto. He has since disappeared and left behind a bitcoin fortune.

Because bitcoin was the first major cryptocurrency, all digital currencies created since then are called altcoins, or alternative coins. Litecoin, Peercoin, Feathercoin, Ethereum, and hundreds of other coins are all altcoins because they are not bitcoin.

One of the advantages of bitcoin is that it can be stored offline on local hardware, such as a secure hard drive. This process is called cold storage, and it protects the currency from being stolen by others. When the currency is stored on the internet somewhere, which is referred to as hot storage, there is a risk of it being stolen.

On the flip side, if a person loses access to the hardware that contains the bitcoins, the currency is gone forever. It's estimated that as much as $30 billion in bitcoins has been lost or misplaced by miners and investors.

Why Bitcoin Is so Controversial

Various events turned bitcoin into a media sensation.

From 2011 to 2013, criminal traders made bitcoins famous by buying them in batches of millions of dollars so they could move money outside of the eyes of law enforcement and tax collectors. Subsequently, the value of bitcoins skyrocketed.

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Scams, too, are very real in the cryptocurrency world. Naive and savvy investors alike can lose hundreds or thousands of dollars to scams.

Bitcoins and altcoins are controversial because they take the power of issuing money away from central banks and give it to the general public. Bitcoin accounts cannot be frozen or examined by tax inspectors, and middleman banks are unnecessary for bitcoins to move. Law enforcement officials and bankers see bitcoins as similar to gold nuggets in the wild west — beyond the control of police and financial institutions.

How Bitcoins Work

Bitcoins are completely virtual coins designed to be self-contained for their value, with no need for banks to move and store the money. Once bitcoins are owned by a person, they behave like physical gold coins. They possess value and trade just as if they were nuggets of gold. Bitcoins can be used to purchase goods and services online with businesses that accept them or can be tucked away in the hope that their value increases over time.

Bitcoins are traded from one personal wallet to another. A wallet is a small personal database that is stored on a computer drive, smartphone, tablet, or in the cloud.

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Bitcoins are forgery-resistant because multiple computers, called nodes, on the network must confirm the validity of every transaction. It is so computationally intensive to create a bitcoin that it isn't financially worth it for counterfeiters to manipulate the system.

Bitcoin Values and Regulations

A single bitcoin varies in value daily. Check places like Coindesk to see current par rates. There's more than $2 billion worth of bitcoins in existence. Bitcoins will stop being created when the total number reaches 21 billion coins, which is estimated to be sometime around the year 2040. By 2017, more than half of those bitcoins had been created.

Bitcoin currency is completely unregulated and completely decentralized. The currency is self-contained and uncollateralized, meaning there's no precious metal behind the bitcoins. The value of each bitcoin resides within the bitcoin itself.

Bitcoins are stewarded by miners, the network of people who contribute their personal computer resources to the bitcoin network. Miners act as ledger keepers and auditors for all bitcoin transactions. Miners are paid for their accounting work by earning new bitcoins for the amount of resources they contribute to the network.

How Bitcoins Are Tracked

A bitcoin holds a simple data ledger file called a blockchain. Each blockchain is unique to each user and the user's personal bitcoin wallet.

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All bitcoin transactions are logged and made available in a public ledger, which ensures their authenticity and prevents fraud. This process prevents transactions from being duplicated and people from copying bitcoins.

While every bitcoin records the digital address of every wallet it touches, the bitcoin system does not record the names of the people who own wallets. In practical terms, this means that every bitcoin transaction is digitally confirmed but is completely anonymous at the same time.

So, although people cannot easily see the personal identity or the details of the transaction, they can see the verified financial history of a bitcoin wallet. This is a good thing, as a public history adds transparency and security to every transaction.

Banking or Other Fees to Use Bitcoins

There are small fees to use bitcoins, which are paid to three groups of bitcoin services:

Servers (nodes) that support the network of miners

Online exchanges that convert bitcoins into dollars

Mining pools

The owners of some server nodes charge one-time transaction fees of a few cents every time money is sent across their nodes, and online exchanges similarly charge when bitcoins are cashed in for dollars or euros. Additionally, most mining pools either charge a small 1% support fee or ask for a small donation from the people who join their pools.

While there are nominal costs to use bitcoin, the transaction fees and mining pool donations are cheaper than conventional banking or wire transfer fees.

Bitcoin Production Facts

Bitcoin mining involves commanding a home computer to work around the clock to solve proof-of-work problems (computationally intensive math problems). Each bitcoin math problem has a set of possible 64-digit solutions. A desktop computer, if it works nonstop, might be able to solve one bitcoin problem in two to three days, however, it might take longer.

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A single personal computer that mines bitcoins may earn 50 cents to 75 cents per day, minus electricity costs. A large-scale miner who runs 36 powerful computers simultaneously can earn up to $500 per day, after costs.

A small-scale miner with a single consumer-grade computer may spend more on electricity than they will earn mining bitcoins. Bitcoin mining is profitable only for those who run multiple computers with high-performance video processing cards and who join a group of miners to combine hardware power.

This prohibitive hardware requirement is one of the biggest security measures that deter people from trying to manipulate the bitcoin system.

Bitcoin Security

People who take reasonable precautions are safe from having their personal bitcoin caches stolen by hackers.

There are two main security vulnerabilities when it comes to bitcoin:

A stolen or hacked password of the online cloud bitcoin account (such as Coinbase)

The loss, theft, or destruction of the hard drive where the bitcoins are stored

More than hacker intrusion, the real loss risk with bitcoin revolves around not backing up a wallet with a fail-safe copy. There is an important .dat file that is updated every time bitcoins are received or sent, so this .dat file should be copied and stored as a duplicate backup every day.

The public collapse of the Mt. Gox bitcoin exchange service was not due to any weakness in the bitcoin system. Rather, the organization collapsed because of mismanagement and the company's unwillingness to invest in appropriate security measures. Mt. Gox had a large bank with no security guards.

Abuse of Bitcoins

There are three known ways that bitcoin currency can be abused:

Technical Weakness: Time Delay in Confirmation

Bitcoins can be double-spent in some rare instances during the confirmation interval. Because bitcoins travel peer-to-peer, it takes several seconds for a transaction to be confirmed across the P2P computers. During these few seconds, a dishonest person who employs fast clicking can submit a second payment of the same bitcoins to a different recipient.

While the system eventually catches the double-spending and negates the dishonest second transaction, if the second recipient transfers goods to the dishonest buyer before receiving confirmation of the dishonest transaction, then the second recipient loses the payment and the goods.

Human Dishonesty: Pool Organizers Taking Unfair Share Slices

Because bitcoin mining is best achieved through pooling (joining a group of thousands of other miners), the organizers of each pool choose how to divide bitcoins that are discovered. Bitcoin mining pool organizers can dishonestly take more bitcoin mining shares for themselves.

Human Mismanagement: Online Exchanges

With Mt. Gox as the biggest example, the people running unregulated online exchanges that trade cash for bitcoins can be dishonest or incompetent. This is similar to Fannie Mae and Freddie Mac investment banks going under because of human dishonesty and incompetence. The only difference is that conventional banking losses are partially insured for the bank users, while bitcoin exchanges have no insurance coverage for users.

Three Reasons Why Bitcoins Are Such a Big Deal

There is a lot of controversy around bitcoins.

Not Created by a Central Bank or Regulated by Any Government

Banks don't log money movement, and government tax agencies and police cannot track the money. This may change, as unregulated money is a threat to government control, taxation, and policing. Bitcoins have become a tool for contraband trade and money laundering because of the lack of government oversight. The value of bitcoins skyrocketed in the past because wealthy criminals purchased bitcoins in large volumes. Because there is no regulation, people can lose out as a miner or investor.

Bitcoins Completely Bypass Banks

Bitcoins are transferred through a peer-to-peer network between individuals, with no middleman bank to take a slice. Bitcoin wallets cannot be seized or frozen or audited by banks and law enforcement. Bitcoin wallets cannot have spending and withdrawal limits imposed on them. Nobody but the owner of the bitcoin wallet decides how the wealth is managed.

Bitcoin Transactions Are Irreversible

Conventional payment methods such as a credit card charge, bank draft, personal check, or wire transfer benefit from being insured and reversible by the banks involved. In the case of bitcoins, every time bitcoins change hands and change wallets, the result is final. Simultaneously, there is no insurance protection for a bitcoin wallet. If a wallet's hard drive data or the wallet password is lost, the wallet's contents are gone forever.