PHP Markdown is a library package for developers that parses text written in Markdown and Markdown Extra syntax, converting it to valid HTML. It's designed for integration into PHP projects where you need to accept user input or write content in a readable plain-text format and publish it as formatted web pages.

• Markdown and Markdown Extra Support: The package includes both the standard Markdown parser and the extended PHP Markdown Extra parser, which adds features like tables, definition lists, footnotes, and attributes for elements.
• Simple Integration: It works with class autoloading (PSR-0 compatible) for easy inclusion in modern projects. You can also use it without an autoloader by requiring specific .inc.php files.
• Static or Instance Usage: Transform text quickly using the static defaultTransform method, or instantiate the parser object directly to customize configuration variables like ID prefixes for footnotes and headers.
• Stable Public API: The public API for the parser classes, their main methods, and configuration is stable within a major version, providing reliability for development.
• Plain Text Focus: The syntax allows content to remain human-readable as plain text while being unambiguously convertible to HTML for web publishing, separating content from presentation logic.