The most popular ways to Authenticate with any Git Server is :

• HTTPS Authentication : Username & Password that you used while registering with Git Server
• SSH : Generate a pair of SSH Keys on the client (passphrase), copy over the public SSH Key on to the Git Server and use Public+Private Key combination for authentication

Before begining any Git Operations from the Client, you would need to configure the Username & Email ID of the Developer who is performing Git Operations. Open up the Git Bash command and type in your Username & Email ID:

$ git config --global user.name "John Doe"  #Double Quote required
$ git config --global user.email [email protected]     #No double quote for email ID
#Check if the settings got picked up correctly
$ git config --list

If your details (username & email ID) are not picked up correctly, do not fret, check if the commands were entered correctly and repeat them any number of times till you get it correctly

• Git 101 Commands
• GitHub SSH Set-Up
• Git Commands Reference
• Vi Editor