You’ve probably heard and also used the terms “e.g.” and “i.e.,” especially in scholarly writing. It’s also possible that you’ve used them interchangeably as many other people do. However, these two abbreviations that actually derive from Latin (and not English) mean different things. It is necessary to use the correct abbreviation to ensure that the meaning of a sentence is retained. 
You mostly use “e.g.” and “i.e.” at the beginning of a nonrestrictive element which is enclosed in either commas or parentheses. It’s also suggested to use a comma after both “e.g.” and “i.e.” 
But let’s have a closer look!

e.g. (exempli gratia)

“Exempli gratia” or “e.g.” is the Latin term for “for example” in English. You typically use “e.g.” to introduce one or more examples of something mentioned previously in a sentence. It’s interchangeable with “for example” or “such as.” Also, don’t forget to use a comma or parentheses to enclose the example list. 

You need many ingredients for a savory chocolate cake (e.g., whipped cream, cocoa powder, and melted dark chocolate).

Don’t forget to keep your belongings close to you on your trip, e.g., your wallet, phone, passport, and some extra money. 

💡 Don’t forget the comma or parentheses.

💡 Don’t use “etc.” at the end of the example list since “e.g.” already implies that there are more examples than you’re listing.

i.e. (id est)

“Id est” or “i.e.” is the Latin term for “that is” in English. You usually use “i.e.” when you want to specify something you mentioned previously. It’s interchangeable with “specifically” or “namely.” And again, don’t forget to use a comma after the term.

Only two kinds of mammals, i.e., the duck-billed platypus and the spiny anteater, lay eggs.

Some of my ancestors came from another country, i.e., Poland and Luxembourg. 

💡 Don’t forget the comma after “i.e.”