The Uchiha were infamous for their especially strong and natural aptitude for anything combat-related, and their proficiency in fire jutsu, having created several and using them more skillfully than any other. Their signature jutsu was the Fire Release: Great Fireball Technique. Clan members are not recognized as adults by the rest of the clan until they can successfully use this.
The Uchiha clan were also most famous for their powerful Sharingan, a Kekkei Genkai which gives them the ability to copy their opponent's jutsu, among other benefits like: enhanced visual perception, the ability to read Genjutsu, Taijutsu and Ninjutsu and then defeat it. Only a select handful of clan members were capable of accessing this power.
Uchiha is another way of pronouncing "uchiwa," a paper fan, which is incidentally the Uchiha clan symbol. Uchiwa can be used to fan flames, making the flame hotter — referring to the fact that the Uchiha is a clan of fire-jutsu users.
