pasting a message instructing someone or a group of people to copy the message and paste it elsewhere (most commonly to all of their contacts)

EXAMPLE: "BIG EMERGENCY YOU ARE GOING TO GET HACKED COPY AND PASTE AND SPREAD THE WORD"
EXAMPLE: "ON APRIL FOOLS WE ARE GOING TO CHANGE OUR PROFILE PICTURES TO DICKS COPY AND PASTE AND SPREAD THE WORD"