I am very new to poker, but i figure just just to test my own reasoning, i'll give my first thoughts (on low limits), and let myself be corrected if i'm wrong.

in playing low limits, I always raise moderately preflop with aa kk. It gets more money into a pot which is probably going to be yours, and it limits limpers gunning for miracles. It puts you in a position of power, you're the raiser. If you call/check preflop, you're more likely to not get taken seriously after the flop, you won't really know anything about what the other guy has, and you're more likely to be chased which i personally don't want happening on just top pair depending on the flop.

i can maybe see some situational uses of limping, but not under usual circumstances. everyone feel free to correct me if i'm wrong, i'm losing money faster than i can count as we speak so i'm probably wrong anyway.