You knew it was coming!
Trope: Fiery Redhead
Description: Unlike her softer-haired counterparts, the Fiery Redhead is as bold as her tresses. She's outgoing and outspoken, with a strong personality that won't let her back down from anything. You do not want to make an enemy out of the Fiery Redhead. She's got a bigger chance of being a tomboy than the Dumb Blonde and the Brainy Brunette, but it's not a necessity for this trope.
Examples: Anne from Anne of Green Gables, Ginny Weasley from Harry Potter, Lucy Ricardo from I Love Lucy
Pros: Brash, passionate characters can be a lot of fun. If someone's known for speaking her mind, there's probably not going to be one of those mangled romance plots riddled with silly misunderstandings that could have been resolved by the characters just TALKING to each other. For better or worse, you always know where the Fiery Redhead stands, and that can be refreshing.
Cons: There can be jokes about the hero needing to "tame" the Fiery Redhead, which is a little too misogynistic for my tastes. Outspoken characters can veer towards being obnoxious if not enough care is taken, and there's a risk of the audience finding her off-putting.
Would/Did I Use It?: You know, I don't think I have used this trope. I've written red-haired characters, but I don't think they fit the stereotypes upon which this trope is based. On the flip side, Ro from Disintegration fits a lot of the characterizations...but she's a brunette. Interesting!