As family name unambiguous defines surname versus last name what name should be used for social friendly name [closed]

Solution 1:

It’s common to refer to a two-part name as consisting of a family name and a given name:

A name given to a person at birth or at baptism, as distinguished from a surname.

(American Heritage Dictionary)

Solution 2:

Talking about what is common in North American English (this actually differs a bit with British English usage):

Certainly Christian name and baptismal name make a lot of cultural assumptions that do not apply to everyone - not everyone is Christian or has been baptized.

Furthermore, even first name does not equal "social friendly name" for everyone. Some people prefer a shortened nickname ("Bob" for "Robert") or a nickname that's unrelated to their first name ("Junior" for someone with the same name as their father). I, personally, use a shortened version my middle name as my "social friendly name" rather than my first name.

Many human resources databases use the term preferred name to indicate the name taht someone wants people to address them with. So you might see an entry like this:

First name: Rafael

Last name: Cruz

Preferred name: Ted

Given that data, formal documents (e.g., tax receipts) would get the first and last name ("Rafael Cruz") but informal emails would get the preferred name (e.g., "Hey Ted, welcome to the team!").