Bitcoin is the world’s first cryptocurrency which works on a completely decentralized network known as the blockchain. The blockchain network consists a link of blocks that are secured using cryptography and record all the transactions. Bitcoin was first presented to the world in 2009 by an anonymous identity known as Satoshi Nakamoto. As Bitcoin works on a decentralized network, it is completely free from the involvement of third-party financial institutions or central banks. The Bitcoin blockchain facilitates instant peer-to-peer transactions at minimum transactions fees required to maintain the network. The total number of Bitcoins is fixed at 21 million with its smallest unit being referred to as Satoshi. Each Satoshi represents a hundred millionth part of Bitcoin which means that 100,000,000 Santoshi = 1 BTC. Additional Bitcoins are generated by a process known as mining. Bitcoins are mined by professional miners solving complex computational equations. For each Bitcoin mined, the miners are rewarded with either more coins or transaction fees. The miners also validate all transactions on the Bitcoin network as well as look after the network security. Bitcoin can be exchanged with fiat currencies or other digital currencies. There are over 100,000 merchants and vendors accepting Bitcoin all over the world.
Coinbase requires you to link a bank account, or credit or debit card to your Coinbase account to purchase cryptocurrencies. Using a bank account allows for higher limits ($100/transaction, $2,500/week), but it also takes longer to verify transactions, so you will not see money in your Coinbase wallet for two to four days (depending on your bank). And when selling Bitcoin, once the sale is confirmed, it takes two to four days for the proceeds of that sale to show up in your bank account. With a credit or debit card, limits are lower ($200/week), but you can purchase digital currencies by simply transferring funds from that bank account to the site. For these transactions, Bitcoin shows up in your Coinbase wallet instantaneously. You can also sell Bitcoin to your PayPal account, effectively cashing out, as your Bitcoin will be exchanged for local currency. This transaction, too, is instantaneous.
In February 2019, Coinbase announced that it had acquired "blockchain intelligence platform" Neutrino, an Italy-based startup, for an undisclosed price. The acquisition raised concern among some Coinbase users based on Neutrino founders' connection to the Hacking Team, which has been accused of providing internet surveillance technology to governments with poor human rights records. On March 4, 2019, Coinbase CEO Brian Armstrong said his company "did not properly evaluate" the deal from a due diligence perspective and thus any Neutrino staff who previously worked at Hacking Team "will transition out of Coinbase."