Is pump and dump bad?

I've often heard of the term 'pump and dump' in the realm of cryptocurrency investing. Could you please elaborate on what exactly it means? Is this a strategy that investors should avoid? From what I've gathered, it seems to involve artificially inflating the price of a coin and then selling it off at a higher price, but I'm not entirely sure. Could you explain the risks associated with this practice and why it's considered unethical or harmful? How does it impact the overall market and the legitimate investors within it? I'm interested in understanding both the technicalities and the moral implications of this practice.