YI BBCode refers to the set of standard BBCode tags supported by the Yiffy International core site and Ychan. The Yforum - Yiffy International's text bulletin board - supports PHPBB BBCode, which is explained in more detail here. BBCode is much like HTML, which uses tags to format text. These tags are not to be confused with the kind of keyword.

• [b]text[/b] - Bold
• [i]text[/i] - Italic
• [u]text[/u] - Underline
• [quote]quote[/quote] - Quotation
• [img]http://url-to-image[/img] - Embed an image
• [url=http://mywebsite.com]title[/url] - Link to a file
• [color=colour][/color] - Set the font colour
• [size=size][/size] - Set the font size