The best way to understand torts is to know a bit of history of England. When the Normans conquered England in 1066, they did not have the manpower to colonize and occupy the entire country. Rather, the new king imposed his land system by appointing barons, and his legal system by appointing judges. These judges would move from town to town (in "circuit"), hearing disputes and applying the king's law. However, at the beginning, the king's law (or "common law") was very skeletal. If the dispute was not an area within the jurisdiction of the judge, then the judge could not decide the dispute. The way to know if the dispute was an area within the jurisdiction of the judge was to read certain pre-approved "writs". If the writ described the circumstances of the dispute, then the dispute could be heard. Each writ developed its own rules on how disputes of that kind should be resolved.
One of the most often used of these writs was known as "trespass vi et armis". That is, the defendant used physical force against the plaintiff. As the king had a monopoly on the legal use of force, the king wished to punish anyone who used force without his authorization.
In the course of history, more writs were created and those that existed became more loosely interpreted, so that common law judges were able to hear almost any dispute. However, the principle remained that common law judges hear certain types of disputes. Each type of dispute has its own set of rules.
A tort, then, is an act committed by one person with negative consequences for another, and which fits in a certain category and judged according to the rules prescribed by the common law. Types of torts include assault, battery, trespass to land, false imprisonment
Up until the 1930s, the only torts recognized in the common law were "intentional torts" (aka. "direct torts"). An intentional tort meant that the plaintiff was the victim of a direct act by the defendant. In 1932, a new tort was recognized in the common law world: negligence. A direct act of the defendant was not a requirement for negligence; all that was required was that the defendant did something that he or she could have reasonably foreseen would harm the plaintiff. Negligence has since become the most litigated tort.
In Quebec, which did not have a common law tradition, the avoidance of actions that the common law would define as torts are considered to be "Obligations". Every person has certain obligations, including the obligation to avoid causing harm to others and the obligation to honour contracts. The Civil Code has a general provision requiring people to avoid harming others, as well as several specific obligations (e.g., parents are responsible for their children, employers for their employees, owners for their pets, etc.) While this is a philosophically different way of approaching torts, and although the reasons judges give for their decisions are remarkably different in Quebec, the end results are strikingly similar.