TinyMCE is a platform independent web based Javascript HTML WYSIWYG editor control released as Open Source under LGPL. TinyMCE has the ability to convert HTML TEXTAREA fields or other HTML elements to editor instances.

The functionality of the Visual (WYSIWYG) post editor typically found on the WordPress Post, Page, and Custom Post edit screens is largely supplied by a Javascript software package called TinyMCE, which is bundled with WordPress.

Sometimes 'TinyMCE' is used to refer to the WordPress Visual Editor as a whole, though technically that is not accurate.