when trying to run a unity game I often get a fatal error, why?

when trying to run a few games on the web that use unity, they stop loading and encounter a error message stating that "the content was stopped because a fatal content error was detected.

This could be from a number of things. Mainly it could be due to a graphics card that doesn’t support them, or your drivers are outdated. Do you have an updated version of the unity web player installed?