# 2-爬虫基础

在写爬虫之前，我们还需要了解一些基础知识，如 HTTP 原理、网页的基础知识、爬虫的基本原理、Cookies 的基本原理等。本章中，我们就对这些基础知识做一个简单的总结。


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://python3webspider.cuiqingcai.com/2-pa-chong-ji-chu.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.