Pump and dump are activities in which someone invests heavily in barely traded crypto, drives up the price (pump) and gets out (dump) when some investors just get in by FOMO, after which the price collapses and many investors become baghodlers. If the dump takes place on one stock exchange, the figures are visible on the sell wall. There are also groups that at an agreed date and time jointly set a pump and dump in motion. Don’t be the last one to place a sale order, otherwise there is a good chance that you will become a baghodler. These groups often come together via different forums, Twitter, Telegram or Slack.