Begging was the act of asking for a handout without expectation of anything in return. One who made a living off begging was known as a beggar.
According to a 49er encountered by Data in 1893 San Francisco, who wanted whiskey, but would settle for a dime, the key to successful begging was: "Stockbrokers are cheap as hell. Don't even bother to ask. Your best handout is from a young fella with his lady. You give him a chance to show her he's generous. Steer clear of sailors. Most likely you'll get a fist across the jaw for your trouble." (TNG: "Time's Arrow")
When Guinan told Q that "You'd better get used to it", after Q was made Human, he asked what she meant, and Guinan answered with the word "begging". (TNG: "Deja Q")