Pump: people buy something (bitcoin in this case) causing the price to go up causing more people to buy - pump up the price
Dump: sell something, presumably before the price drops again.
That's what it looks like. But this is really what happens - mainly in these groups of pump and dump:
A group of limited people buy cheap shitcoins for X price and make all the other poor and dumb people (who wants to profit with those schemes) to buy them thinking that they will profit in a short amount of time. Of course, the price of the coins rise because there are a lot of people buying them in a short amount of time. But what they don't realize is that only a few people can profit with this (the ones who bought before the price rise).
When the price reaches X*2 (or more), the limited group of people sell all their accumulated coins into the other people heads, making the price crash.
Result:
- the limited group of people got richier.
- a lot of dumb people are stuck with bags of shitcoins.
TLDR: Don't participate in pump and dump groups/schemes.
