Some business people are confused about when to use i.e. as opposed to e.g. The abbreviation i.e. is from the Latin phrase id est. It means that is. On the other hand, ?e.g. is from the Latin phrase exempli gratia, meaning for example.
When deciding which one to use, think in terms of inclusiveness. If you want to indicate everything following, use i.e. If you mean just some of the items, use e.g.
You must be tested in computer programs, i.e., Lotus Notes, Word and Excel (all the programs).
You must be tested in computer programs, e.g., Lotus Notes, Word and Excel ?(some of these programs).
Punctuation: The Canadian Press Stylebook requires periods between the letters. Also, note that there must be commas before and after the abbreviations.