The BBCodeParser class works the same way as the HTMLParser class, except it parses BBCode, which is a bit simpler, so some complexity was removed.
BBCode was created for providing a safer and simpler format for formatting post on forums. It is very similar to html.
For example: [code][b]This text should would be bold if this bbcode was interpreted.[/b] [size=14]This text would have a font size of 14.[/size] etc.[/code]