What's your name?

This post describes different ways of asking name of a person and telling your name.

You can ask someone's name with Wie ist Ihr Name, bitte?
This expression literally means "What is your name, please?"
The answer to this question can be Mein Name ist XYZ

Another way of asking someone's name is Wie heissen Sie?
Wie means "How", heissen means "to be called as" and Sie is formal case for "you". Hence this expression can be translated as "How are you called as".
The answer to this question can be Ich heisse XYZ.

The expression Wer sind Sie? can be used to ask name. This means "Who are you?"
The reply for this question can be Ich bin XYZ which means "I am XYZ".

The above three expressions formal ways of asking someone's name.

Wie heisst du? also is used to ask someone's name, but this is used in informal context. The reply to this question can be Ich heisse XYZ

Vocabulary from this post (click on the word for more information):

Wie	How
ist	Is
Ihr	You
Name	Name
bitte	Please
Mein	My
Heissen	to be called as
Wer	Who
Ich	I