Writing Tip 6: Affect or Effect?

What is the difference between 'affect' and 'effect'?

Answer: although both words can be used as verbs and nouns, usually affect is used as a verb and effect as a noun:

The film affected everybody. (= affect, verb)

The film had a powerful effect on everybody. (= effect, noun)

'Affect' indicates feelings or change; 'effect' indicates results or consequences.

Only 'effect' can be followed by the preposition 'on'. 'Affected' is often followed by the preposition 'by':

I was profoundly affected by what I saw.

'Effective' is a very common adjective for describing how something has 'affected' you:

The film had a very effective ending.


'Effect' is also used as a verb, though it is not common. It means 'to cause' or 'to bring about':

The new management effected some important changes in the first three months.

'Affect' can be used as a noun, but is not commonly used in everyday speech. It refers to the area of psychology concerned with feelings.