Although i.e. and e.g. are fairly ubiquitous little linguistic gadgets, both non-fluent and native English writers can find themselves mixing them up occasionally.
If you see that a client has definitely mixed up i.e. and e.g., you should correct the issue in the text. You do not need to leave a comment unless you are not sure (from the context) whether the term has been used incorrectly.
Launch the microlearning module below to learn more about i.e. and e.g. and to test your knowledge using our interactive quiz.
Alternatively, read on for a text-only version of the microlearning.
That Is (i.e.)
The term “i.e.” means “that is.” It is used to introduce supporting information about or a definition of a point that has just been made. For example:
- My brother was always seen as the golden (i.e., favourite) child.
- I tried all four flavours of ice cream available on the menu (i.e., vanilla, pistachio, salted caramel, and double chocolate).
- The results of the survey are too general, i.e., they do not consider the client’s specific needs.
For Example (e.g.)
The term “e.g.” means “for example.” It is used to offer some select examples supporting a point that has just been made.
Unlike those given by i.e., the examples following e.g. should not cover every eventuality or option. For example:
- My brother was always seen as the golden child. This was shown in various ways, e.g., he always got the biggest slice of cake at birthday parties.
- There are about 10 flavours of ice cream on the menu (e.g., baked turnip, sour cream) that don’t sound very appealing.
- The results of the survey were too general, e.g., Table 4 of the analysis looked at the entire sector’s turnover, not just that of the client’s company.
A Couple of Notes on Usage
There are a few other things you should be aware of when using i.e. and e.g.
Commas
US English includes a comma after i.e. and e.g., UK and Australian English do not usually do so.
Etc.
You should not include “etc.” at the end of a list preceded by e.g. or i.e.
This is because, by using e.g., you’re saying you’re only offering select examples (so it stands to reason that there are more). By using i.e., you’re saying that you’ve listed all possible examples (so there shouldn’t be any more).
Alternatives to i.e. and e.g.
In recent years, especially in online content, the terms i.e. and e.g. are falling into disuse. This is due to various accessibility issues (e.g., screen readers read them incorrectly).
Potential alternatives to i.e.: that is, in other words, consisting of.
Potential alternatives to e.g.: for example, including, such as.
Periods
The vast majority of dictionaries and style guides punctuate i.e. and e.g. with periods.
A notable exception to this is the legal referencing system OSCOLA: due to its hatred of unnecessary punctuation, it writes them as ie and eg.
Summary
To summarize: i.e. is used when you want to define or list all options for something, e.g. is used when you want to give some select examples.
