2. Steve Urkel (Family Matters)
Generic sitcom "Family Matters" began life as a spin-off of hit sitcom Perfect Strangers, intended to focus on popular police officer Carl Winslow and his family. Then 12 episodes in, a one-off character debuted who took the entire world by storm like Bart Simpson. Though looked back on now as an annoying and overbearing character who commandeered the show and made it ridiculous, at the height of it's popularity Urkel was highly beloved, and the responsibility for that feat fell squarely in the lap of one Jaleel White. Jaleel almost instantly endeared himself to the audience with his nerdy mannerisms and amusing antics. While today such a character would be rightly considered a creeper or a borderline stalker for refusing to accept rejection, Steve's love for Laura was always seen as harmless, annoying puppy love. Urkel quickly became the primary focus of the series, to the point where today many people remember it as "The Urkel Show". The interaction between him and Carl was often the main focus, with the pair constantly getting involved in whacky hijinks either because of Steve's clumsiness or Carl not listening to Steve's advice. Another reason Urkel took off was due to Jaleel's surprising versatility as an actor, frequently getting to play different versions of himself. His Bruce Lee impression has to be seen to be believed.