There have been many Robins that Batman has raised and trained to become his sidekick and fight his worst enemies with him.
The first one was Dick Grayson. Dick was an acrobatic with his family, they were the Flying Grayson’s. Until one day Dick’s family was murdered and he had to go to foster care. Batman eventually adopted him and he became the first robin.
The next one is Jason Todd. Unfortunately Jason was murdered by the Joker and then resurrected by Ra Al Gul and then became the Red Hood because he wanted to kill Batman for leaving him with the Joker to torture him for a year.
The third one is Tim Drake. Tim Drake was another person who lost him family and was then raised by Batman and became the third Robin and then left batman to go lead the Teen Titans.
The final Robin is Damian Wayne. Yes Damian is Batman’s son. The mother is Talia Al Gul, Ra’s daughter. Damian is not the most loyal Robin because all he wants to do is murder the criminals for what they did. But that is not what Batman does and they eventually came to an agreement.
There are more robins but those the most famous robins. But by far my favorite Robin is Dick Grayson. He is so loyal to Batman. He then eventually became Nightwing and protects Keystone City.