Character from the
Marvel Comics universe. He first appeared in Amazing
Spider-Man #9.
Max Dillon worked on power lines for the city. One day, while working on the lines, he was struck by lightning. The shock did not kill him, but instead bestowed upon him great electricity-manipulating powers. (Go figure.) What sort of powers, you may ask? He found himself able to fire bolts of electricity, surround himself with electrical energy that would shock anyone who touched him, and even the ability to fly. He decided to use these powers for crime, which promised to make him more money than fixing power lines ever did. He performed bank robberies, jewel heists, and other random villainous acts. Nothing too megalomaniacal. Occasionally, he would join a team of supervillains (for the company, I suppose). He was an original member of the Sinister Six, and belonged to the Frightful Four for a while as well.
Over the years, it's become very clear that Electro has a giant self-esteem problem. This was probably caused by an often-alluded-to mother, who often berated Max, and dominated every aspect of his life. During the Light Up the Night storyline from Spider-Man #38-40, Electro decided to attempt tapping into the city's power supply to increase his superpowers. It was an effort to show everyone that he was a major player in the super-villain world, but his self-doubts got the best of him. He tapped into the city's power grid and nearly used all of that power to kill himself. Spider-Man intervened, and saved his life. Electro seemed to feel better about himself, and for a while it looked like he might turn his life around.
But rather than take the opportunity he had to change his life, he became resentful of Spider-Man's interference. In his mind, Spider-Man kept him from going through with his plan to become more powerful. So he tried again, with some help from the Rose. He recreated the situation which gave him superpowers (with an electric chair instead of power lines) and indeed, became much more powerful than before. Drunk on his new power, he went on a bit of a rampage, humiliating Spider-Man as well as almost leveling New York City. He was stopped, but you can't keep a good supervillain down. Electro is now colder and more ruthless than ever before. He's intent on moving up in the crime world, and his power makes it likely that he'll succeed, as long as he can keep his neuroses in check.