2 Factor Authentication is a double layer security measure. Most crypto exchanges use it. In order to log in, you not only need to enter a password, but also a code that you receive from the Google authenticator for example.
Launched in 2015, Ethereum is the world's programmable blockchain. Like other blockchains, Ethereum has a native cryptocurrency called Ether (ETH). ETH is digital money. People all over the world use ETH to make payments, as a store of value, or as collateral. But unlike other blockchains, Ethereum can do much more.
The block reward is the payment that is offered to the node that is securing the blockchain. In the case of Bitcoin, which is has a Proof-of-Work consensus algorithm, these would be the miners. The payment is in the form of the native cryptocurrency of that blockchain. The amount is a predetermined reward per block, but often that is supplemented with the fees that are paid for the transactions that block contains. For Bitcoin the current block rewards are cut in half every four years. This is called the ‘halvening’.
An altcoin is any cryptocurrency or token created after the Bitcoin was developed.
With digital currency, there is a risk that the holder could make a copy of the digital token and send it to a merchant or another party while retaining the original.
Blockchain is most simply defined as a decentralized, distributed ledger technology that records the provenance of a digital asset.
