What's the difference between i.e. and e.g.?
mid-12c., "young man attendant upon a knight," from Old Norse sveinn "boy, servant, attendant," from Proto-Germanic *swainaz "attendant, servant," properly "one's own (man)," from PIE *swoi-no-, from root *swe- "oneself, alone, apart" (see idiom). Cognate with Old English swan "shepherd, swineherd," Old Saxon swen, Old High German swein. Meaning "country or farm laborer" is from 1570s; that of "lover, wooer" (in pastoral poetry) is from 1580s.