(If any of this is incorrect, don't be afraid to let me know.)
There are three main schools of Karate: those derived from the acrobatic/long-ranged Northern Kung Fu (Shorin-ryu), those derived from the less-mobile/close-ranged Southern Kung Fu (Shorei-ryu), and those derived from the very springy/ballistic Western Kung Fu (Korean styles).
Shorin-ryu styles include Shotokan, Wado-ryu, and Kyudokan. Their training results in a quick, mobile fighter. Their kata - Kushanku and Gankaku being excellent examples - reflect this, featuring speedy, sometimes acrobatic techniques.
Shorei-ryu styles include Goju-ryu and Uechi-ryu. Their training is intended to harden the individual into a close-ranged fighter. This is apparent in kata such as Sanchin and Seisan, with the movements showing a clear emphasis on close-range, hand-based combat.
Western Kung Fu - particularly Tan Tui - influences Tang Soo Do, Soo Bahk Do, and Tae Kwon Do to be styles that ditch speed in favor of sheer power. The Chilsung/Yukro set of kata exemplify this, although this preference for power is evident in nearly every Korean style; TSD/SBD hyung, as well as ITF and WTF forms, show a clear emphasis on slow, powerful movements. The fact that these styles focus on kicking - which by itself is a slower, more powerful alternative to punching - further reinforces this. These styles also seem to require more flexibility, with ridiculously deep stances and high kicks being part of the training.
If anyone reading this is trying to decide on a style to learn, this is my advice:
-If you are a small, fast person with a high endurance, find a Shorin-ryu school.
-If you are a bigger, stronger person, find a Shorei-ryu school.
-If you are a flexible person, find a Korean school.
-If you are an older person or if you want to practice a more "gentle" martial art purely for health reasons with a very low injury risk, I would specifically recommend Soo Bahk Do, as it isn't as brutal/intensive as the other arts yet features a good blend of hand and foot techniques to keep yourself fit/flexible while also becoming a decent fighter. And it's forms look absolutely beautiful, but that's just my opinion.
