Afternoon Delight is a daily diversion for when you’re just back from lunch, but not quite ready to get back to work. Check back tomorrow at 1 p.m. for another one.

Annoyed by some repeated image, video clip or sound bite cropping up in every blasted website you visit (the scary hamster, people planking)? You may have wondered: What does it mean, where did it come from and why does my adolescent kid find it so absolutely hilarious? Or to quote Grandpa Simpson: “I used to be with it, but then they changed what it was. Now what I’m with isn’t it, and what’s it seems weird and scary to me. And It’ll happen to you.”

Well, in the great tradition of PBS earnestly over-explaining our world so it won’t seem remotely scary, the PBS Arts Off Book series has produced this little instructional defense of web memes, animated GIFs, re-mixes and mashups like the NYAN cat.