Spelling Auto Correct

I'm not sure if this has to do with my browser, my operating system, or the boards themselves, but I've only noticed this issue when I'm on the boards here.

When I'm making posts, an auto-spell correction occurs, very similar to the one on my i-phone. Every time I write out "nerf" the auto correct changes it to "nerd" and "nerfing" is always switched to "nerving."

Please help, -Thanks