The first article is about blockchain and the concept of virtual currency.

Blockchain, it's a compound word. One is a block and the other is a chain.

Block, refers to the collection of data, specifically on Bitcoin, refers to a block discovered by miners, the transaction data after the release of the previous block and before the release of the block, packaged into the block.

Chain, chain of blocks. Each block contains a hash value that is carried up by the chain of all previous blocks, so the chain is irreversible (see below for bifurcations).

Blockchain + virtual currency, to put it bluntly, is an irreversible and unchangeable data chain (tampering costs too much). The chain contains all the virtual currency transaction information, and solves the problem of untrustworthiness between strangers in the network by means of data encryption. Because the source code of the software is open source, and Bitcoin is mirror node data, all the data, everyone downloaded a copy, basically eliminating the possibility of cheating.

Bitcoin source code address: github.com/bitcoin/bitcoin

The second article begins with a step-by-step analysis of Bitcoin source code to unlock the mystery of Bitcoin.