The sorcerer is an arcane spellcaster who draws power from some inner source.
For a full list, see Category:Sorcerers.
Prior to Dungeons & Dragons 3rd edition, "sorcerer" was sometimes used as a synonym for "wizard" or "magic user". In Original Dungeons & Dragons, sorcerer was a level title for 9th level magic user. However, it did not refer to a separate class until third edition.
The sorcerer class first appeared in the D&D third edition Player's Handbook (2000). In this edition, the sorcerer shares its spell list with the wizard class, as well as most of its class features (e.g. d4 hit dice, low base attack, and the ability to summon a familiar).
The primary difference between sorcerer and wizard in third edition is how they learn and cast spells. Sorcerers have a limited pool of spells known, and do not keep spellbooks. They may spontaneously cast spells from any that they know using empty spell slots, and do not need to prepare the spells in the slots ahead of time.
Sorcerers also have more spell slots than wizards, gaining up to six per spell level compared to the wizard's four. However, their major drawback is that their acquisition of new spell levels is delayed by one character level compared to the wizard. For example, a fifth level wizard can cast the third level spell fireball, but a sorcerer must wait until they are sixth level to learn or cast the same spell.
A sorcerer's power is speculated to come from some source like draconic heritage, but unlike later editions, this is largely for flavour and has no game rule effect.
Sorcerers did not appear in the initial 4th edition Player's Handbook (2008), but were introduced in Player's Handbook II (2009). In this edition, which largely abandoned the Vancian spellcasting system, sorcerers are differentiated from wizards by being a striker class, which deals high damage to individual targets, rather than the wizard's controller class, which prefers spells that attack multiple opponents. The two classes have separate spell lists.
A sorcerer's power explicitly derives from a Spell Source, most commonly either Dragon Magic, from some connection to dragonkind, or Wild Magic, from a connection to the Elemental Chaos. Arcane Power (2009) adds two new sources: Storm Magic, and Cosmic Magic.
In 5th edition, sorcerers possess two key class abilities: Sorcerous Origins, which grant unique special abilities based on the source of the sorcerer's magic, and Sorcery Points, which can be exchanged for spell slots or spent to perform metamagic. Metamagic is exclusively a sorcerer ability in 5th edition, in contrast to earlier editions where it was available to all spellcasters.
The sorcerer has a separate spell list from the wizard, made from a reduced subset of spells available to the wizard, with a focus on combat spells. For example, only five different 9th level spells in the Player's Handbook (5e) (2014) are available to the sorcerer (Gate, Meteor Swarm, Power Word Kill, Time Stop and Wish), while the wizard can cast all these and seven others.
Stories of men and women who wield magic appear throughout mythology and in numerous fantasy novels and video games which inspired Dungeons & Dragons. Spellcasters in D&D traditionally followed a system inspired by the works of writer Jack Vance, in which spells were memorized or prepared once and spent when cast. This contrasted with most video games, where a spell can be repeatedly cast as long as the character has sufficient mana points.
The writers of D&D 3rd edition were given a wide berth to make changes to the traditional rules, allowing them to create a new, more dynamic non-Vancian spellcaster variant. It may have been inspired by the sorcerer class from Diablo (1996), which informed what many new D&D players would come to expect from an offensive spellcaster.