Important: Python crawlers work with strings all the time, so it’s important to know strings, especially when extracting data

STR and bytes:

STR: in Unicode form, which we can intuitively understand

Bytes: Displays data in binary format. All data is transmitted on the network in binary format, which is hard to understand

ASCLL:

A byte represents a character, which occupies a small memory, but cannot completely represent the characters of all countries. Each country has different codec methods, which makes it difficult to use

Unicode:

Two bytes are used to represent one character, occupying large memory, which can represent almost all characters, but occupying large memory is difficult to promote

UTF-8:

1. Unicode is an implementation of Unicode, which can be understood as an upgraded version of Unicode.

2. Automatic recognition of the number of characters, can use any byte to represent a character, is a variable length encoding method, and select the smallest byte

3. Make the memory use optimal and can represent all characters

Praise the utf-8!!!!!