e.g. vs. i.e. (Grammar Rules)
Let’s look at the differences between e.g. and i.e. with Grammar Rules from the Writer’s Digest editors, including a few examples of correct usages.
The abbreviations of i.e. and e.g. are often used in written and spoken language, but what's the difference between these two abbreviated Latin phrases? One is used to show examples, while the other gives further elaboration, but it's not uncommon to find them misused.
So let's look at the differences between e.g. and i.e. and when to use each.
E.G. vs. I.E.
E.g. is an abbreviation of the Latin phrase exempli gratia, which itself means "for example." This abbreviation is used in language to take the place of that phrase for the sake of concision (i.e., four characters for "e.g." instead of 11, including the space, for "for example").
I.e., on the other hand, is an abbreviation of the Latin phrase id est, which itself equates to the phrase "that is" or "in other words." Again, this abbreviation is used in language to take the place of that phrase for the sake of concision (e.g., using e.g. instead of "for example").
Make sense?
Here are a few examples of e.g. and i.e.:
Correct: Joey wanted some hot food, e.g., soup or a stew.
Incorrect: Joey wanted some hot food, i.e., soup or a stew.
Correct: Joey wanted some hot food, i.e., food with a hot temperature.
Incorrect: Joey wanted some hot food, e.g., food with a hot temperature.
For many writers, this may feel like splitting hairs, because I know people who may say they think it's OK to use "that is" in the first incorrect example and "for example" in the second incorrect example. And it's true that many people would probably be able to figure out what was meant, but both instances would still be incorrect.
There's a pretty simple trick for keeping these terms straight: Take the "e" in "e.g." to remember the phrase "for 'e'xample;" and use the "i" in "i.e." to remember the phrase "'i'n other words" or "that 'i's." That's all there is to it.
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No matter what type of writing you do, mastering the fundamentals of grammar and mechanics is an important first step to having a successful writing career.

Robert Lee Brewer is Senior Editor of Writer's Digest, which includes managing the content on WritersDigest.com and programming virtual conferences. He's the author of 40 Plot Twist Prompts for Writers: Writing Ideas for Bending Stories in New Directions, The Complete Guide of Poetic Forms: 100+ Poetic Form Definitions and Examples for Poets, Poem-a-Day: 365 Poetry Writing Prompts for a Year of Poeming, and more. Also, he's the editor of Writer's Market, Poet's Market, and Guide to Literary Agents. Follow him on Twitter @robertleebrewer.