The basis of blockchains are blocks. These are small units of data containing transactions that account for all transactions in a given period of time. If you transfer some crypto, your transaction will likely be included in the next block. Blocks are mined and added to the chain, creating a blockchain. Each block validates the block before it, thus maintaining a single, permanent or immutable version of the truth. The size of the block determines how much data can be stored on it and the frequency of the blocks or block times determine how many blocks are produced in a given time. The blockchain should contain every single transaction ever made since the beginning of the blockchain.

A web interface that allows users to query the contents of the blockchain, like a search engine for the blockchain. Information on the blockchain can be searched like transactions and addresses balances.

A service that facilitates the transfer of coins or tokens from one L1 blockchain to another or from L1 to L2. For example from Ethereum to BSC or from Avalanche to Fantom.

Where a service is provided by a business running a central order book, hosting on central servers and generally run by one or a small group of individuals with decision making power. The opposite of decentralized.

This is the method by which a blockchain decides on a single state of the network as well as which transactions and blocks to add to the chain. Because blockchains are operated by a large number of distributed anonymous nodes, there must be a way to guarantee that all nodes agree on the same information. There are many different consensus mechanisms but most require that participants risk something in return for the ability to add blocks to the chain and receive rewards. They are rewarded for keep the network operational and punished for adding false or inaccurate information. The most popular consensus mechanisms are Proof of Work and Proof of Stake. In proof of work, miners risk time and electricity to try to mine the next block. In proof of stake, validators risk capital by staking their coins. If they contribute to the efficient running of the network they are rewarded, if they do not they are "slashed" and their capital is reduced.