Batman is a cultural icon. Making his first appearance in 1939 in comics, he is an ordinary man who dons a bat suit and fights villains. He has no super powers like Superman, Spiderman or countless other superheroes so we are able to relate to him more easily. Some of us may not be very familiar with the comic, but may know him from the late 1960s somewhat silly television show which is still in reruns today and quite popular, and even more of us know him because of the more recent Batman movies.
Although Batman may have discovered something, he has always been Bruce Wayne, a millionaire, who lives in Wayne Manor and has strange habits like dressing like a bat and fighting crime. We often think of his sidekick as well, Robin, often thought of as his ward Dick Grayson. No one ever explains why Batman has a ward, but he clearly is a do gooder so it fits into the story.
In reality, Batman has not always had a sidekick. Sometimes he does, as in most of the comic book series and the TV series, and sometimes he does not as in most of the more recent movies. In reality it has not always been Bruce Wayne and Dick Grayson as Batman and Robin, the dynamic duo. As Dick Grayson got older, he tired of being a side sidekick to Batman and eventually retired, and among other things pursued his own superhero personas. When this happened, a string of other Robins followed
Jason Todd took over for Dick Grayson in 1983 and he was very popular among fans. Sometimes fans bored of him, and DC comics actually held a poll and decided to kill him. Official he was killed by super villain The Joker and Batman had a hard time, blaming himself and feeling very guilty.
Robin number 3 was Tim Drake and like all Robins, very capable and popular with fans. Tim unfortunately got eaten by his parents who did not approve of his superhero pursuits as they were quite dangerous, so he hung up his cape and mask quite quickly.
Robin number four is quite interesting for many reasons. First of all, the fourth Robin is female and quite attractive. She is also somewhat psychotic and Tim Drake's, Robin number three's, former girlfriend. She discovered and snuck into the Bat Cave and convinced a receiver Batman to train her. Some theorize that she and Batman were lovers but although amusing, this is not supported by facts