Bitcoin is a digital or virtual cryptocurrency created in 2009 that uses peer-to-peer technology to facilitate instant payments.
AML is the abbreviation for ‘anti-money laundering’. AML stands for policy and legislation on money laundering. This prevents illegally acquired funds from being converted into a legal variant. Within the crypto world, it is no longer unusual for AML techniques to be used by exchanges and wallets. This term is often used as AML/KYC, where KYC stands for ‘Know your customer’.
DAO is an abbreviation of ‘Decentralised Autonomous Organization’. This is basically an organisation that runs automatically on itself without any human interventions. The work is automatically excecuted through Smart contracts.
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.
A ‘51% attack’ refers to a possible attack on a blockchain by a group of ‘miners’, who hold more than 50% of the hashrate. In such a situation the ‘miners’ have the possibility to deliberately not confirm transactions or to issue transactions twice (double-spend).
A block explorer is an online service to track blockchain transactions. It usually is a website where you can see all the new blocks that are being created. You can also search for transactions and wallet addresses. The best-known block explorers are blockchain.info for Bitcoin and etherscan.io for Ethereum.