What's the difference between i.e. and e.g.?
late 14c., "act of reciprocal giving and receiving," from Anglo-French eschaunge, Old French eschange (Modern French échange), from Late Latin excambium, from excambiare, from Latin ex- "out" (see ex-) + cambire "barter" (see change). Practice of merchants or lenders meeting to exchange bills of debt led to meaning "building for mercantile business" (1580s).
late 15c., from Old French eschangier "exchange, barter," from Vulgar Latin *excambiare (source of Italian scambiare); see exchange (n.). Related: Exchanged; exchanging.
exchange ex·change (ĭks-chānj')
v. ex·changed, ex·chang·ing, ex·chang·es
To substitute one thing for another. n.
The act of substituting one thing for another.