The abbreviation ‘e.g.’ comes from the Latin exempli gratia, which means ‘for example.’
The abbreviation ‘i.e.’ comes from the Latin id est, which means ‘that is.’
Great. So what does that mean?
Use ‘e.g.’ to precede items that are examples of the term that precedes it but not necessarily an exhaustive list.
Example: Green vegetables (e.g., broccoli and asparagus) are good for you.
Explanation: Broccoli and asparagus are examples of green vegetables, but there are other green vegetables, such as Brussels sprouts and green beans.
Use ‘i.e.’ to precede an item or items that rename the term that precedes it.
Example: The mother convinced the toddler to eat his little trees (i.e., broccoli).
Explanation: The mother told the child he was eating little trees, a ‘toddler’ term for broccoli, which allegedly makes them more palatable for children.
Always follow ‘i.e.’ or ‘e.g.’ with a comma.
Never use ‘etc.’ with either ‘i.e.’ or ‘e.g.’