Should I use (I.e.) or (E.g.)?
Properly used, each of these is Standard. I.e. abbreviates Latin id est, 'that is'; use it when you wish to repeat in different words what you've just finished saying: I'm strongly opposed; i.e., I'm determined not to cooperate. E.g. abbreviates the Latin tag exempli gratia, 'for the sake of example, for example.' People sometimes say the names of the letters i and e or e and g instead of saying the English that is or for example, but the abbreviations aren't much shorter, and most of us would prefer the English words in speech, no matter how familiar the Latin abbreviations are in writing. Most editors put them in italics; all require a comma after the second period.
0 Q, 109 A, 0 C