Basically, what Ambivalence and MrXxx said. Satan, in the Book of Job (supposed to be the oldest book in the Bible, so presumably reflecting an older stratum of belief) is God's 'counsel for the prosecution', if you like; his job is to prove that humans deserve God's wrath. Only later on does he actually tempt people.
The idea of angels having 'fallen' is a separate strand, found largely in the apocryphal Book of Enoch (which is later, from the last couple of centuries BCE), but mentioned in that passage in Genesis where the 'sons of God' come down and marry the 'daughters of men', resulting in giant hybrid children. Those angels were seen as teaching humans 'evil' arts (like metalwork, writing, herbal medicine and the use of eyeshadow!), and were punished by God; various names are given (the leader was Azazel, who later had the 'scapegoat' of Jewish ritual dedicated to him), but Satan isn't among them. The 'bright morning star' passage in Isaiah 14 probably refers to one of several possible Mesopotamian kings, and was only later identified with Satan.
I think the idea of Satan is a tricky one. Either you accept that, as in Job, Satan is one of God's personal staff, therefore under God's direction; or that he's rebelled, but God can't or won't deal with him. It strikes me as rather as if you worked for a company where the boss let a renegade executive go round scamming various subordinate employees into doing the wrong thing, and rather than deal with him, the boss fires them. Basically, he appears to be a device to either let people themselves off the hook for the bad stuff they do, or to let God off the hook for the evil in the world. The question you have to ask is: in a perfect heaven, what could have made Lucifer want to rebel?
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"Grunge? Isn't that some gross shade of greenish orange?"