My screen's color is all out of whack.  My email is black and pictures look like a negative image from old film strips.  What is going on?
___________

Sounds like someone accidentally enabled the Color inversion feature in Universal Access. That feature is designed to assist people with sight impairments. It’s an easy fix.

Go to system preferences then select universal access. You’ll see the option to choose black on white or white on black under the Display listing.

That should take care of it.