Do you know someone who has never seen a "Star Wars" movie, watched an episode of the cartoons, or read a "Star Wars" book or comic? Chances are, they know who R2-D2 is.

The astromech droid R2-D2 has been a staple of "Star Wars" from the start and has gone into popular culture with R2-shaped Pepsi containers, appearances on "Sesame Street" and "The Muppet Show", and thousands of pencils, stickers, and notebook covers.

Until the Prequel Trilogy (1999-2005) we didn't really know the little droid. Oh, we THOUGHT we did. He was C-3PO's sidekick, he restored the hyperdrive to the MILLENNIUM FALCON, and he brought the Death Star plans to the Rebel Alliance. OK, even though he wasn't organic he was a hero in most anyone's book (as fictional characters go). However, in the words of 9-year-old Anakin, "That's not the half of it!"

It turns out in R2's brief period as Padme's droid and then Anakin's it seems he discovered several key secrets to the universe. Unlike Threepio, there was no order to have R2-D2's memory erased. I would assume this was because R2 units were not known for their long-term memories. R2 units were intended to fix computers, but Anakin programmed the droid to do much more. He very likely was responsible for improving the droids memory.

So that takes us to the Original Trilogy (1977-1983). We now know that, unlike Threepio, R2 wasn't in the dark about what had occurred in the past. He likely realized the R5-D4 unit, presumably older and cheaper, would be competition for him. He also certainly recognized the name "Skywalker" and figured Luke could take him to Obi-Wan. It can be surmised that R2 did something to destroy R5-D4's motivator.

Furthermore, when R2 met Obi-Wan for the first time in twenty years I imagine he had some kind of programming that would enable him to age-progress the image of Kenobi he had in his mind. Therefore, when R2 whistled and Obi-Wan said, "Hello there", they both knew who they were addressing.

Throughout the Original Trilogy it seems that R2 prods his organic companions (and his peer, C-3PO) into situation that will lead them to their destinations.

I like to think of it like this; in the Prequels the Emperor was in control. In the Originals, R2-D2 was.