What does it mean when I get this symbol?

It seems to me to be an Unknown Error sign because every time I get it I don't know why. And all I know is its an Error sign. So I'm assuming its an Unknown Error sign. The only time I get it often is When I'm playing this one game I forgot the name to and who its made by.

It's a processing sign. Basically, it shows up when it gets stuck on one place in the code for a while, whether it be the game loop or somewhere else.