'Memes' are internet crazes - pictures, animations, videos - that are usually sent via email.
Perhaps the most famous are the LOLcats, pictures of cats with deliberately ungrammatical and misspelled captions, telling you what the animal would be thinking if it were human: 'I can has cheezburger?'
Meanwhile, people around the planet are dancing something called the Harlem Shake. Not all the nonsense circulating the internet is a true 'meme'. Technically, the point of a 'meme' is that it is not just passed on but imitated.
Biologist Richard Dawkins invented the word in 1976 to describe ideas, skills, tunes, catchphrases and other cultural phenomena that spread by imitation, deriving it from mimema, the Greek for 'a copy'.
And what has this to do with business? Well, you can try to invent your own - not easy, though it worked for Old Spice in 2010 - or you can imitate famous meme imagery in your marketing.
But beware: these days, everyone has a lawyer.