Difference between "affect" and "effect"

Affect
"Affect" is used as a verb and means "to have an influence on".

• His decisions could affect the lives of millions of people. 
• The accident will affect the value of the car.

Effect
"Effect" is usually used as noun and  means "the result".

• The effect of the tsunami was devastating. 
• The defeat had a terrible effect on the team's spirits.

"Effect" can also be used as a verb meaning "to bring about".

• The present government effected many positive changes.

Exercise 1