Effect and Affect

An effect (noun) is a result.

The medicine had no effect.

The medicine did not work.

To effect (verb) means to bring about a result.

The manager hoped the meeting would effect a change in employee behaviour.

The manager hoped the meeting would cause the employees to change their behaviour.

To affect means to influence or to make a difference to something.

Sam's illness began to affect his work.

Sam's illness changed how he worked.