This is a list of characters in the Tom and Jerry cartoon short series. Most of these characters did not appear in all of the movies.
Tom (named "Jasper" in his debut appearance) is a grey and white domestic shorthair cat. ("Tom" is a generic name for a male cat. He is usually but not always, portrayed as living a comfortable, or even pampered life, while Jerry (named "Jinx" in his debut appearance) is a small, brown, house mouse who always lives in close proximity to Tom. Despite being very energetic, determined and much larger, Tom is no match for Jerry's wits. Jerry also possesses surprising strength for his size, approximately the equivalent of Tom's, lifting items such as anvils with relative ease and withstanding considerable impacts. Although cats typically chase mice to consume them, it is quite rare for Tom to actually try to consume Jerry. Most of his attempts are just to torment or humiliate Jerry, sometimes in revenge, and sometimes to obtain a reward from a human for catching Jerry. By the final "fade-out" of each cartoon, Jerry usually emerges triumphant, while Tom is shown as the loser.
However, other results may be reached. On rare occasions, Tom triumphs, usually when Jerry becomes the aggressor or when he pushes Tom a little too far. In The Million Dollar Cat Jerry learns that Tom will lose his newly acquired wealth if he harms any animal, "including a mouse;" he then torments Tom a little too much until he retaliates. In Timid Tabby Tom's look-alike cousin pushes Jerry over the edge. Occasionally and usually ironically, they both lose, usually when Jerry's final trap or attack on Tom backfires or Jerry overlooks something. In Chuck Jones' Filet Meow, Jerry orders a shark from the pet store to scare Tom away from eating a goldfish, but finds himself entirely intimidated as well. Finally, they occasionally end up being friends, although within this set of stories, there is often a last minute event that ruins the truce. One story that has friendly ending is Snowbody Loves Me.
Both characters display sadistic tendencies, in that they are equally likely to take pleasure in tormenting each other, although it is often in response to a triggering event. However, when one character appears to truly be in mortal danger from an unplanned situation or due to actions by a third party, the other will develop a conscience and save him. Occasionally, they bond over a mutual sentiment towards an unpleasant experience and their attacking each other is more play than serious attacks. Multiple shorts show the two getting along with minimal difficulty, and they are more than capable of working together when the situation calls for it, usually against a third party who manages to torture and humiliate them both. Sometimes this partnership is forgotten quickly when an unexpected event happens, or when one character feels that the other is no longer necessary. This is the case in Posse Cat, when they agree that Jerry will allow himself to be caught if Tom agrees to share his reward dinner, but Tom then reneges. Other times however, Tom does keep his promise to Jerry and the partnerships are not quickly dissolved after the problem is solved.