Since HBC has members from many different countries and backgrounds, we have opted not to provide spellchecking as part of our text editor.  You are free to spell colour as color (or color as colour) depending on your preference.
Most users do not worry about spellchecking their forum or blog posts (this isn't homework, after all!). For those who can't live without spell checks, there are some handy browser plugins available which will add support for spell checking to all your web sites:

  • For Internet Explorer, try IESpell
  • Firefox 2 or newer include a spell checker by default, but you may need to install a dictionary.
  • Safari 3 or newer includes built-in support for spell checking