What is a tort? It sounds like it could be some kind of food, but it is actually a civil wrong. That means that a victim has a civil cause of action against the wrongdoer. It may or may not be that there is a potential criminal cause of action (which is brought by the people, not an individual) for the same conduct. Individuals or businesses can sue or be sued under the law of torts. A tort can be intentional or unintentional. Intentional torts include assault, intentional interference with economic relations or with contract, or intentional infliction of emotional distress. Unintentional, or negligent, torts, include negligent infliction of emotional distress, and negligent interference with economic relations.
The most famous issue in the tort realm is negligence. Negligence results when someone has a duty to another person, their conduct falls below (or breaches) that duty, the conduct causes a problem (like an accident) and someone is damaged because of it. When there is a car accident arising out an individual running a red light or speeding, a person can sue another because the person sued had a duty (to not speed, to follow traffic signs) that they breached, and their conduct falling below that duty caused damage. Whether you are talking about car accidents, assault (physical, sexual), or other conduct, a tort is often the route to civil liability against a wrongdoer, or someone on whose the behalf the wrongdoer acts.