Bitcoin (BTC) is a decentralized digital currency invented by Satoshi Nakamoti and launched in January of 2009.
It relies on cryptography to secure and control the coin units. The use of cryptography has lead to it being described as a crypto-currency or simply "crypto". It uses a blockchain as a ledger for registering the transactions of the coin units. It uses peer to peer to distribute the blockchain and transactions.
Bitcoin is a preferred currency among criminals because of the lack of traceability. The authorites have been sitting idle and letting this currency flourish. The problem with Bitcoin is that it enables hi-jacking, piracy, kidnapping, extortion, hitjobs, prostitution and drug-dealing on a large scale that has never been seen before. With all of these illegal activities also comes the problem of tax evasion. Many countries around the world miss out on needed tax funding for health and education.
There are a number of ways to trade and speculate in Bitcoin. There are a number of crypto-currency exchanges that lets users buy the crypto currencies and transfer it off the exchange to their own wallet. There are also a number of exchange traded funds on traded on regular stock exchanges that can be bought for exposure to the Bitcoin price. There are also derivatives traded through many Forex brokers that can be bought for exposure to the Bitcoin price.