affect, effect

'Affect', used as a verb, means to influence. 'Effect', used as a verb, means to cause.

Affect, used as a verb, means to influence. Avoid using affect as a noun (used in psychology to describe an emotion). The CEO's positive attitude affected the entire staff.

Effect, used as a verb, means to cause. Used as a noun, effect means result. The new CEO effected change soon after he started. The effect of the California Community Colleges Scholarship Endowment on Community College students is yet to be seen.