Comic Sans is a computer font designed by Vincent Connare while he worked at Microsoft fifteen years ago.
Based on comic strip lettering, it gives a light-hearted edge to text, and is very popular.
That's bad news according to husband and wife team Holly and David Combs, who run a web site called bancomicsans.com.
They are fed up with seeing Comic Sans in the wrong places and launched their campaign 8 years ago to attempt educate people in proper font selection.
The BBC invited the couple and the designer on to World Update in order to discuss the pros and cons of Comic Sans.
Dan Damon started by asking Holly to describe the font:
First broadcast 23 April 2009