The abbreviations e.g. (from the Latin exempli gratia) and i.e. (from the Latin id est) are often confused. This is because they are both used to introduce some clarification of something previously mentioned.
The abbreviation e.g. is used to provide an example:
• The restaurant has a wide variety of foods, e.g., vegetarian and non-vegetarian soups, Italian and French cuisine, and down-home American fare.
• He was accomplished at many sports (e.g., tennis, golf, baseball, and long distance runnning).
The abbreviation i.e. is used to restate an idea more clearly or offer more information.
• It happened in April, i.e., two months ago.
• A service charge is included in all prices; i.e., you don’t have to leave a tip.
Getting Them Wrong
Often mixing the abbreviations up does not mean your sentence is grammatically incorrect. However, getting them wrong will change the meaning of your sentence.
• All amphibians are thriving in the new pond; e.g., the two bullfrogs were being very active yesterday.
• (This sentence is fine grammatically. From it, we infer that there are more amphibians than two bullfrogs in the pond.)
• All amphibians are thriving in the new pond; i.e., the two bullfrogs were being very active yesterday.
• (This sentence is fine grammatically. We infer that the only amphibians in the pond are the two bullfrogs.)
This may assist in remembering:
• e.g. = “example given”
• i.e. = “in effect”