Cheerio is an HTML and XML parsing library and server-side DOM implementation. It functions as a markup manipulation tool and CSS selector engine, allowing users to parse, query, and modify HTML or XML documents in non-browser environments.
The project provides a DOM-like tree representation of markup strings, enabling programmatic addition, removal, and modification of elements and attributes. It features a prototype-based plugin system that allows the extension of core functionality by adding custom methods to the document prototype.
The library covers a broad range of capabilities including CSS selector querying, recursive tree traversal, and element collection filtering. It also includes utilities for attribute manipulation, CSS class management, node positioning, and the rendering of manipulated trees back into serialized HTML or XML strings.