You'll see this from time to time and it means that your PC has crashed and it's time to restart your computer and hope that you remembered to save your work recently. There's no answer, no meaning, something to do with the computer trying to use the same bit of memory to do two things at once - duh! We love it really, makes life exciting.
The error code you get when a Windows program causes a failure or lock-up. It can be due to insufficient memory, a buggy program, incompatible drivers, or hardware problems.
Windows term - Each program running under windows is given its own exclusive area of memory which is protected from other applications & a general protection fault occurs if this exclusive memory is accessed by another program.