Used in an expression in some languages, this operator yields a boolean result, i.e., true or false. In others (like C) it returns an integer. Check the documentation of the language you are using to find out how it handles true/false values. A mathematical example:
5 >= 10 would evaluate to false whereas
10 >= 5 would evaluate to true
Also known as ≥ in some circles.
You can represent these symbols in HTML by means of the following HTML symbol references: >= or ≥ or ≥.
Thanks to mblase, C-Dawg, and Inoshiro_K and others for keeping me straight on the finer points.