"Find out how the changes will effect you" proclaims the banner on the website for soon-to-be-closed phone retailer Crazy John's. This means Crazy John's customers who already face an uncertain future now have proof that the team at Vodafone can't even be bothered to use accurate spelling when communicating with them.
Confusing 'affect' and 'effect' is a very common error. The difference is a simple one: 'affect' is the verb, and 'effect' is the noun. As such, "Find out how the changes will affect you" is the correct version. Those changes might have an effect on which carrier you choose.
Yes, pedants, I know; 'affect' is used as a noun in psychology, and you can deploy 'effect' as a verb in a sentence such as "I plan to effect some changes". But those are outlier cases that won't help the linguistically confused, and the word 'make' would be a better choice in the second example.
Indeed, if you can't readily tell if you've used the correct spelling when selecting between 'effect' and 'affect', using a different word is the best strategy. Had Crazy John's written 'Find out what these changes mean for customers', we wouldn't be having this discussion. Accuracy matters, and simplicity helps accuracy.
Thanks Joshua for pointing out the Crazy John's error. You'd think a company which must have suffered from years of horrendous apostrophe abuse would know better.
Lifehacker's Mind Your Language column offers bossy advice on improving your writing.