A single letter separates affect and effect, but that one letter makes a big difference. Here’s a quick explanation between the two words:

Affect is (usually*) a verb. It means to have an impact on something, to influence, or to produce a result. Here are some examples:

• This rain is going to affect our crops if it doesn’t let up soon.
• Please don’t let her bad mood affect yours.
• One minor traffic accident affected the schedule of everyone on the freeway.

*I say “usually” because in obscure cases affect can be used as a noun, meaning an emotional response (“a blunted affect”). I rarely see this usage, however.

Effect is (usually**) a noun. It means a result or consequence, an influence. Here are some examples:

• The effect of all that rain was a spoiled crop.
• Her bad mood had little effect on yours.
• The effect of one minor traffic accident was a lot of missed appointments.

**I say “usually” because effect can also be used as a verb when it means “to bring about.” A typical phrase in this use case is when someone (usually a politician) talks about “effecting change.”

I know this can be complicated to wrap your head around, and I promise you’re not alone if it’s giving you trouble! I’ve found that a good trick for remembering the difference between the most common uses of affect and effect is this:

Affect begins with an A, and effect begins with an E. A comes before E in the alphabet, and you need to AFFECT something before you can have an EFFECT.

I hope that explanation is effective!

-Maria

This blog post originally appeared on CreateSpace.com. Reprinted with permission. © 2015 CreateSpace, a DBA of On-Demand Publishing, LLC. All rights reserved.