What does the french word demander mean?

Demander is a very common Word with many uses, but the basic equivalent in English is ask for. For example:

Kevin is asking his sister for a piece of paper. -- Kevin demande une feuille de papier à sa sœur. (Notice that the person being asked is the indirect object, and the thing being asked for is the direct object.)

Another common usage is in the reflexive (se demander), which literally means to ask oneself but is often better translated as to wonder.

Je me demande pourquoi il est lÃ. -- I wonder why he/it is here/there.