Differences in Usage

In general, affect is a verb and effect is a noun. When X "affects" Y, it is said that X produces an "effect" on Y. In passive form, Y is "affected" by X.

As a rule of thumb that works in most common usage scenarios, it is advisable to use affect as a verb (transitive, intransitive, active, passive) and to use effect as a noun.

Like many other words in the English language, affect and effect have more than one meaning.

When used as a noun, "affect" refers to the external display of one's emotions or moods. The pronunciation of the word "affect" is slightly different when used as a noun. It is pronounced with a short A, as in apple, rather than the "uh" sound found in amount and affect when used as a verb. For example, consider the sentence John was unaffected by the impassioned performance. This means John did not display any emotions.

When used as a verb, "effect" means to execute, produce, or accomplish something. It is pronounced the same way whether used as a verb or a noun. For example: The best way to effect change in society is to work at the grassroots level. Here "to effect change" means "to produce change".

The word "effects" can also be used to mean "a person's belongings". For example, He left without any of his personal effects.