Gamers Glossary: Hex

Hex, Hexes:

Breaking from the traditional square playing spaces, many games are instead played on fields made up of regular hexagons instead, this approach has extended from the wargames in which it started, into all types of games. They are known as hexes for short.
The advantages of hexes over the traditional squares approach is that there are more moves possible, since there are six sides, and the corners are also used to good effect in the Settlers of Catan series.