Thomas "Tom" Cat is a fictional character and one of the two titular main protagonists (the other being Jerry Mouse) in Metro-Goldwyn-Mayer's series of "Tom and Jerry" theatrical animated short films. Created by William Hanna and Joseph Barbera, he is a grey and white anthropomorphic domestic short haired mute tuxedo cat who first appeared in the 1940 MGM animated short "Puss Gets the Boot". The cat was known as "Jasper" during his debut in the short; however, beginning with his next appearance in "The Midnight Snack" he was known as "Tom" or "Thomas".

His name, "Tom Cat", is based on "tomcat", a word which refers to male cats. He is continuously after Jerry Mouse, for whom he sets traps, many of which backfire and cause damage to him rather than Jerry.

Tom has changed over the years upon his evolution, especially after the first episodes. For example, in his debut, he was quadrupedal. However, over the years, he has become almost completely bipedal and has human intelligence.

More Info: en.wikipedia.org