Effect and affect are often confused because of their similar spelling and pronunciation. The verb 2affect usually has to do with pretense.

    • she affected a cheery disposition despite feeling down

The more common verb 3affect denotes having an effect or influence.

    • the weather affectedeveryone's mood

The verb effect goes beyond mere influence; it refers to actual achievement of a final result.

    • the new administration hopes to effect a peace settlement

The uncommon noun affect, which has a meaning relating to psychology, is also sometimes mistakenly used for the very common effect. In ordinary use, the noun you will want is effect.

    • waiting for the new law to take effect

    • the weather had an effect on everyone's mood