If you haven’t heard of the term ‘meme‘, Wikipedia defines it as:
An Internet meme (/?mi?m/ meem) is an idea, style or action which spreads, often as mimicry, from person to person via the Internet, as with imitating the concept.
See them all on Meme Gallery.

Mass Communications Academic, @MMUBS. British Home Front Propaganda posters as researched for a PhD completed 2004. In 1997, unwittingly wrote the first history of the Keep Calm and Carry On poster, which she now follows with interest.