Okay, that's a pretty terrible way to describe it.
The way the system works is like so:
- Transactions are encrypted messages that are broadcast into the Bitcoin network. The network is a peer-to-peer system, similar to Bittorrent. Transactions only specify a Bitcoin address and transfer of ownership of bitcoins is via these addresses.
- Every ten minutes a bundle of transactions, called a block, is verified through a process called mining.
- Mining is a process that involves trying to figure out the encryption key used on the transaction using brute force. A block is considered mined when the key contains a signature that the system is looking for called the target difficulty. For example, the target difficulty could be the last 20 bits of the key has to be 0. On average over time, a computer would have to generate at least 2^20, or about a million, keys. Once a key that meets the target difficulty is found, it's added as a proof of work.
- Once a block is verified, it's grouped into block chains, which are added to a public transaction database. This data based is shared across the Bitcoin network.
- For every block verified, the miner gets 12.5 bitcoinsnote as a reward. This is also how new coins are added into circulation.
The bitcoin itself is something of a strange entity, since this implies that bitcoins are really records of validated transactions. The symbol for the bitcoin is ฿
Once block chains are verified, they cannot be changed without redoing the work. And as long as honest nodes who are verifying blocks are outpacing those who are trying to attack the system, then the system remains stable. This led up to something of an arms race, where people would develop customized chips designed to compute the algorithm. Every so often, the target difficulty is adjusted so that the process of mining keeps the 10 minute target time.
In any case, Bitcoin is something of a hot topic. Some businesses have accepted it as a valid form of payment. Governments around the world, though, are mixed since it has legitimate and illegitimate uses. Read up on the legal status of Bitcoin as well as Bitcoin's need-to-know FAQ before thinking about getting into the wonders of cryptocurrency.
Just so you don't go out rushing to get mining equipment, note the following:
- Bitcoins are highly volatile. One minute they may be worth something like ฿1 = $1; the next, ฿1 = $0.01. That is, don't expect this to be another source of stable income.
- As with all currency conversion exchanges the relative value of two currencies is based on what people are willing to pay for it. However unlike national currencies where the bulk of the trading is done by banks and other financial institutions most Bitcoin trading is done by individuals or small organizations so the lower volume leads to more volatility.
- Bitcoins can be lost, often with no way of tracking their existence or proof of ownership, with no recourse such as pressing charges with police or filing a lawsuit. Nor are bitcoin exchanges guaranteed or capable of error correction as, say, banks or stock exchanges are if your monetary loss is the fault of the exchange itself due to hacking or even internal criminal activity. A good example of this is the losses in the Mt. Gox exchange bankruptcy the bitcoins are either in the pockets of hackers or simply wiped out, and anyone who was still using Mt. Gox is most likely SOL.
- Bitcoins are not legal tender; you can't pay taxes with them directly. Well, not in every state.
- Bitcoins, depending on your country's tax laws, are taxable income since they can carry legitimate value (they can be exchanged for goods and services, in the same way regular money can).
- Some governments may instead treat Bitcoin and other virtual currency as property. This comes with all of the rights and limitations that the government's property laws afford. That is of course, if you can prove you own them.
- Bitcoin mining is such a developed hobby that to make a decent amount off mining takes a lot of real-world money. Among other complications, US$500 graphics cards and even costlier ASIC boards will need to mine coins for years before recouping the investment at the current rate of things. Without specialist processors, miners are very likely to pay more in electricity costs than they will gain in bitcoin.
- For that matter, a lot of large bitcoin mining operations search out cheap power, to the point that Plattsburgh, New York put a temporary ban on new operations due to the fact that it has ultra-cheap hydroelectric power *up to a fixed amount* and the resulting overages - with the local utility having to buy that power on the spot market - had a devastating impact on the community (like many places with cheap hydro, electric baseboard heat is common).
- The currency itself has a cap of 21 million bitcoins and as of July 2016, 15.75 million (75% of total supply) have been mined. Every four years the rate of creation is halved.note
Bitcoin has so far led to another cryptocurrency called Litecoin. The key differences are that Litecoin transactions are processed every 2.5 minutes; it uses a proof-of-work algorithm called scrypt, which makes it harder to build ASICs that accelerate the work, and the expected cap is 84 million coins. Litecoin also has a derivative cryptocurrency called Dogecoin. And yes, it's a legitimate cryptocurrency. Bitcoin has also seen its fair share of derivatives, and many other types of cryptocurrencies hoping to be the spiritual successor to bitcoin are also starting to flood the market. Will any of them succeed? It's too soon to tell.