A Beggar is a player usually a lower level that begs for free items. Beggars usually never receive anything good and are just ignored by the players they are begging. If a beggar does get something it is probably something useless. Some beggars will take off all of their armor so they look like they have less money. Sometimes begging turns into pointless spam which can be reported under Rule 1.
Sometimes, a "beggar" will think of a reason to need the item, be it valid or not, and use that to make players feel sorry for them and give them items. Some possible reasons include "I've just been killed and need armor" or "It is my birthday and you need to give me something." One of the most common things that beggars say is "I just got hacked" or a variation. This may be true, but most of the time it is not. There has also been times when players use auto typers to get free items and others have continually followed high-level players and constantly annoying them until they give the beggar items. A better course of action in this scenario, if you cannot put up with it, is to change worlds or teleport.