Tae Kwon Do or Karate?

If you are thinking about doing a martial art for self defnse, dont do Tae Kwon Do or Karate. They are really more self-esteem builders than anything else. If you really want to learn to defend yourself and do some actually intense physical activity, try boxing (or kickboxing), muay thai, or brazilian jiu jitsu. Judo is also good. If you REALLY want to learn how to defend yourself I'd recommend brazilian jiu jitsu (BJJ). Its a lot ground fighting and submissions that would be really helpful to you because 1) a lot of real fights go to the ground 2) They let a weaker person defeat someone larger 3) you dont have to rely on strength as much as skill. In a real situation a girl like you w not a lot of strength isnt going to be able to fend off anyone with strikes: theyll just walk through your punches and grab you or something. So from a self defense perspective Id say do BJJ. Its been called the most effective self defense form by many, its physically intense (help you get in shape), and its fun. Also if you question its effictiveness just go watch a UFC fight. Pretty much all MMA fighters train in BJJ. If this isnt what youre actually looking for though and you just want a martial art for fun like taekwondo or karate, Id say do karate. Its at least better than taekwondo, where every 5 year old has a blackbelt.