Colours in 6 digit hex format

I have to say something about beta companies.  I am trying out HipCal this morning with its tres cute hippo logo -- the site is designed to help you manage your calendar, your tasks and your contacts. Seems reasonable enough. AND then I run into a serious snag for a baby geek.  I want to create a new category for my tasks list and then they ask for a colour.  But not any colour.  I write red -- it tells me that "Color must be in 6 digit hex format.  Example:  #3366FF".  I google for this information and can't easily find it.  I then go to Wikipedia and find this article about