Are similar to viruses except that instead of having to attach themselves onto something to spread, worms can live on their own and spread through channels like the network.

Google IT Support Professional Certificate Course 5
IT Security: Defense against the digital dark arts

This course will help you understand:
- how various encryption algorithms and techniques work as well as their benefits and limitations.
- various authentication systems and types.
- the difference between authentication and authorization.
- how to evaluate potential risks and recommend ways to reduce risk.
- best practices for securing a network.
- how to help others to grasp security concepts and protect themselves.