in reply to Ignoring nodes
A prime example would be posting "Python is so much better than Perl!" It wouldn't matter whether the poster really believed that; he would write it because he knows it'll stir things up.
Someone who responds to such a post is said to have been trolled.
Also see troll in the Jargon File.
A photo of people (family, friends, myself, ...)
A photo of my pet(s)
A photo of something man-made (cars, machines, etc.)
A photo of nature, space, or something else not man-made
An abstract pattern
Artwork, digital or photographed
A solid color
A digital animation
Whatever my desktop environment has set for me by default
I haven't seen my background in weeks, too many windows covering it!
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