Commutes supports (some) bbcode which means that you can format posts through tags that will make them stand out and look fancier. If you add your text within a tag, the corresponding formatting will be applied to it (for example [i]Hello World![/i] will result is Hello World!).
Not really a tag but you can mention people with @username.
Anything in between [b] and [/b] will get bold.
Anything in between [i] and [/i] will get Italic.
Anything in between [u] and [/u] will get Underline.
Anything in between [s] and [/s] will get a Strike.
Anything in between [size=number] and [/size] will get a size change, keep in mind that size should be greater than 9 and less than 30, size 10size 29.
Anything in between [url] and [/url] will get converted to a URL, for custom URL titles, [url=URL] TITLE [/url] is used.