How do hackers use bots?

How do hackers utilize bots in their nefarious activities? Are these bots specifically designed for hacking purposes, or are they repurposed from legitimate software? What techniques do hackers employ to control and coordinate these bots, and how do they ensure their anonymity while carrying out attacks? Additionally, what are some of the most common types of attacks that hackers launch using bots, and how can individuals and organizations protect themselves from such threats?