Explain five cyber security best practices, and for each one, explain what it is, why it is used, how it is used

Explain five cyber security best practices, and for each one, explain what it is, why it is used, how it is used (not expected to implement but be able to explain), and an example on the context (organization, any security domain) where it can be used. Number the best practices as i, ii, iii, etc. so that I can clearly identify them.