First, the history of the development of programming languages
1, machine language
Machines can understand the language, binary, 0,1,0,1 ...... direct the operation of the underlying hardware language. High efficiency, development efficiency bottom, cross-platform poor.
2, assembly language
Binary by English characters, the operating system directly, but also the underlying language, the efficiency is slightly lower, the development of high efficiency, cross-platform poor.
3, high-level language
Is human language, logic, high efficiency, low development efficiency, cross-platform.
High-level language is divided into: compiled languages and interpreted languages
Compiled : such as c, c ++, php language, the entire file compiled by all, not a one of the execution, there is a problem you have to re-compile, write code from scratch.
Interpreted : such as c #, java, Python, code can be written in a one of the execution, errors can be changed immediately.
Compare:
Development efficiency : Interpreted> Compiled> Assembly language> machine language
Efficiency : interpreted <compiled <assembly language <machine language
Cross-platform : Interpreted> compiled
So, python is a high efficiency of the development of cross-platform interpreted language.
Two, python introduced
python has two meanings, one is the grammar of the language style, one is to interpret the language style of the interpreter.
1, python interpreter
Version Category:
1. python 2.x (not maintain official 2020)
2. python 3.x
2, python installation
Official website installation
3, python code executed in two ways
Interactive:
Command line:
4, IDE tools
(Python charm) dedicated tool to write python code
Benefits: to enhance the development efficiency
Disadvantages: Comparison of memory resources
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