Affect and Effect

Affect and effect

Probably the two most confused words in the English language!

Affect is used to describe an influence or cause of change and not the result of it. Affect means to bring about a change, to move emotionally, or to infect, as a disease.

Effect means consequence, outcome, upshot. Its central meaning is something brought about by a cause. You can affect an effect, but cannot effect an affect.

Additionally, an affect can have many effects.

The volcanic ash cloud affected the air quality for hundreds of miles; with poor visibility, delayed flights, and acute respiratory problems being some of the effects reported.

(The volcanic ash cloud caused the air quality to change, which led to poor visibility, delayed flights and acute respiratory problems.)

There is an increasing tendency in modern English usage to replace affect with impact, impacted, or impacting. However, this is only of limited use since, impact also means collision or the force transmitted when two objects collide, it also means to pack tightly.

Although it can be a useful guide to determine whether you should write affect or effect, its use should be sparing; especially when the correct use of affect will give your writing more impact! Consider the logic and effectiveness of the following:

It will be a long time before we know what affect the meteor's impact had on the moon.

It will be a long time before we know what impact the meteor's impact had on the moon.