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1. Dick Grayson
In Detective Comics 38 (1940), Batman takes in eight-year old Dick Grayson, a circus acrobat whose parents were murdered by crooks, and grooms him to become his sidekick, Robin the Boy Wonder (not named after the bird, but after Robin Hood). Comic sales doubled, as Robin mediated the grim harshness of the Caped Crusader and gave the kids someone to identify with, and soon every superhero in the business had a young boy tagging along.
Robin soon became a teenager, and fought crooks alongside Batman. During the 1960s he founded a superhero coalition, the Teen Titans, who listened to rock music and said "groovy" a lot.
In the 1980s, all grown up, Dick Grayson decided to set off on his own as the superhero Nightwing. Thereafter he and Batman occasionally worked together, and in at least one storyline, he returned temporarily to his Robin persona.
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After Dick Grayson moved on, Batman needed a new sidekick. He chose Jason Todd, a troubled kid who he had been mentoring since 1983. Unfortunately, fans never took to the new Robin; after a reader poll in 1988 called for him to be dropped, the writers obligingly had him murdered by the Joker. He later was resurrected as the superhero Red Wing.
3. Tim Drake
Never at a loss when it came to finding young boys to mentor, in 1989 Batman brought in Tim Drake, who had been a fan of the original Dynamic Duo. But this Robin was not satisfied with merely hanging out with an old guy; he formed his own teen superhero coalitions, Young Justice and then the new Teen Titans full of millennials.
You may have noticed that all of the Robins look pretty much alike. Batman definitely has a type.
In 2011, Tim Drake left Batman to become the superhero Red Robin, and retconned his past to insist that he had never been just plain Robin.
4. Stephanie Brown
A Girl Wonder?
Yep, Tim Drake's girlfriend (not shown) took up the mantle of Robin briefly. Then she became the Spoiler, then Batgirl. Then she was retconned to have never been any of them.
5. Damien Wayne
The next Robin was Batman's son, raised by the murderous League of Assassins, and thus quite a handful when he came to live with Dad. Eventually he settled down to fight crime as Robin, then Red Bird, before being murdered. Or, in an alternate reality, becoming the new Batman.
But the thing about being a twink magnet is, there's a new crop every year. A few hours of cruising at Gotham City Junior College, and Batman will be soon be taking the next Boy Wonder by the...um...hand.