What are the necessary settings for "git configuration"?

What are the necessary settings for "git configuration"?

when I create a project in Xcode 4.3 it keeps on displaying message saying
below.I did not get what that means and how to do the necessary settings.
Any help will be greatly appreciated. Thanks Baha
Please tell me who you are
Run
git config --global user.email
"you@example.com"
git.config --global user.name"Your
Name"
to set your account's default identity.
Omit --global to say the identity only in
this repository.
fatal:unable to auto-detect email address
(got 'Home@s-imac-3.(none)")`