The "final girl" theory

The "final girl" theory consists of a `plucky' female protagonist who fights all the way to the end of the narrative. The theory derived from  Carol J. Clover’s 1987 essay 'Her Body, Himself: Gender in the Slasher Film,'-  later included by Clover in her hugely influential book "Men, Women, and Chain Saws: Gender in the Modern Horror Film" where final girls are named as the survivors of slasher/horror/sci-fi films. Also, the book looks at how the male gaze effects the final girl theory as well as contemplating on how subversion of this theory is rare in the film industry. The key point made is that male viewers who make up the majority of those who view slasher films cheer on both the victimisation of women and their triumphant kill the final stages of the narrative. The final girl theory therefore shows that both women can empathise with the heroin due to identification and men can both lust over through "male gaze"/voyeurism and admire the final girl for the protective and heroic "male like qualities" that she possess.
Here's a little something I found that sum's the theory up:

BENNY:     But I still want to know what happens!
BUFFY:     Everyone gets horribly killed except the blonde girl in the nightie, who finally kills the monster with a machete but it’s not really dead.
JENNIFER:     Oh, my God. Is that true?
BUFFY:     Probably. What movie is this?

(from the TV series, Buffy the Vampire Slayer)

Clear examples of the "final girl" can be found in films such as Ridley Scotts Alien (1979) and John Carpenters Halloween (1978) Where we see females with very different characters who both triumph over the male killer. Rambo, the female heroin in alien (played by Sigourney Weaver) is a very strong headed female who is physically strong as well as determined to carry out her designated job throughout this alien attack. This could echo the strong, modern, professional female that society recognises today. On the other hand, Laurie Strode (played by Jamie Lee Curtis) is a virginal, bright girl in her teens; the epiphany of innocence. Laurie attacks Mike Myers with a knitting needle and shows through body language that she is extremely scared when she is being attacked. These actions could represent a week female but her triumph shows femininity in a powerful light.