Time Lord names a member of the oligarchic rulers of the planet Gallifrey, the Gallifreyans. Less frequently in the Doctor Who BBC television series they are referred to as Lords of Time or Chronarchs. Gallifreyans possess one the oldest and mightiest civilisations in the universe. As the Time Lords, they held absolute power for some ten million years. Intervention by all thirteen incarnations of the Doctor placed the Time Lords in suspended animation.
The Gallifreyan life cycle has not been well defined, except that they are excpetionally long lived. However, the Eleventh Doctor once said to a group of humans, "We were all jelly once. Little jelly eggs, sitting in goop," indicating that Gallifreyans began as ovum similar to mammals on Earth. Source: The Rebel Flesh. As with humans, Gallifreyans may be male or female. In an amusing British-ism, female Time Lords were sometimes referred to as Time Ladies.
The Time Lords had a rite called Soul Catching, which was done to dying Time Lords before they were assimilated into the Matrix. This allowed them to assimilate their memories before they died. Once they reached extreme old age, Time Lords are permitted to retire on another planet. Salyavin or Chronotis is the only Time Lords known to taken up the offer. When a Time Lord eventually died, either through the exhaustion of their regenerations or through circumventing the regeneration process, it was considered necessary to destroy their corpse soon afterwards.
One of the major institutions of the Time Lords was the Time Lord Academy. Children began instruction at the age of 8 with a special ceremony. The Gallifreyans would be forced to look into the Untempered Schism, which showed the entirety of the Time Vortex and the power that the Time Lords had. See Fictional Universities and Colleges.
Being superbeings does not freee them from politics and the Time Lords were led by the High Council consisting of the Lord President|Lord or Lady President, Lord Chancellor|Lord or Lady Chancellor, Castellan and Lord Cardinal|Lords Cardinal.
The Inner Council consists of the three most powerful members of the High Council. The Lord President was the most powerful member of the Council and had near absolute authority, and used a link to the Matrix, a vast computer network containing the knowledge and experiences of all past generations of Time Lords, to set Time Lord policy and remain alert to potential threats from lesser civilisations. Gallifreyan civil servants were all equipped with a psychic tripwire to prevent them from revealing confidential information. Should any of this information be revealed, the tripwire was triggered leading to the civil servant suffering psychic seizure leading to eventual death.
Protection of the Time Lords was carried out by the Chancellery Guard, who defend the Capitol, investigate crimes and capture criminals. Tens of thousands of years before the Doctor Who's time, criminals were trapped in Shada prison, with the intent being that they would be kept there until a suitable punishment could be decided. By the Doctor's time, this method had been phased out and replaced with disintegration.