Vorname
In short
A Vorname is a given name used to identify a person within a family or social group, distinct from their surname.
In plain words
It is the first name you are given at birth. In most Western cultures, it comes before your family name. It helps people tell you apart from other members of your family.
A simple example
In the name Johann Sebastian Bach, Johann Sebastian is the Vorname, while Bach is the surname.
Why it matters
It establishes an individual's identity separate from their lineage. In many cultures, it is the primary way friends and colleagues address one another.
Easy to mix up
Do not confuse it with a surname, which identifies your family group.