Of all the classic Latin abbreviations, i.e. and e.g. are no doubt the most popular. But they are also the most confused for one another.
Thankfully, the editor of Merriam Webster Online has come forward to clear up any confusion. He explains that the abbreviation i.e. stands for id est, meaning that is, while e.g. stands for exempli gratia, meaning for example.
A simple trick is to remember i.e. and that is both contain an ‘i,’ while e.g. and for example both share a beginning ‘e.’