A MEME is a term borrowed from genetics that refers to "a unit of identification."
In marketing a MEME separtes one idea from another by using images, words, sounds, graphics, etc to convey an idea and hopefully emblaze that idea into the mind of the reader/listener.
During the World Series game one, Ebay unleashed it's new MEME which is simply IT. The tag line is "What ever IT is, you can get IT on Ebay."
Of course the IT graphic is in the famous Ebay primary colors. MEMEs make ideas memorable for sure.
In this case, a couple of primary colors and 10 words help us learn what Ebay is all about.