This Mac tip is provided by Mark Greentree and was originally posted on Mark’s blog – Everyday Mac Support. For more of Mark’s tips visit his site, follow him on Twitter, or browse his archive of posts here.
Do you use the Universal Access features of your computer.
If so you may use the display setting which allows you to invert your display to present a white on black representation.
You can quickly switch between display options by pressing Command-Option-Control-8.
Likewise, to return to the normal display by simply pressing the above keys again.
This tip is hopefully useful to anyone suffering visual difficulties.