Doom is a series of first-person shootervideo games developed by id Software. The series focuses on the exploits of an unnamed space marine operating under the auspices of Union Aerospace Corporation (UAC), who fights hordes of demons and the undead in order to survive.
Doom is considered to be one of the pioneering first-person shooter games, introducing to IBM-compatible computers features such as 3D graphics, third dimension spatiality, networked multiplayer gameplay, and support for player-created modifications with the Doom WAD format. Since the release of Doom in 1993, the series has spawned numerous sequels, expansion packs, and a film.
Since its debut, over 10 million copies of games in the Doom series have been sold.
In November 2012 publisher Haymarket Media Group announced that Atomic would close and be merged into sister monthly title PC & Tech Authority (beginning with the February 2013 issue of PCTA), although the Atomic online forums would continue to exist in their own right and under the Atomic brand.
With a small team of writers led by magazine founder and ex-editor Ben Mansill, who is also the founder of the magazine's only competitor, PC Powerplay, the first issue of Atomic was published in February 2001. This team consisted of John Gillooly, Bennett Ring, Tim Dean and Daniel Rutter. Gillooly and Ring later left the magazine.
In concurrent programming, an operation (or set of operations) is atomic, linearizable, indivisible or uninterruptible if it appears to the rest of the system to occur instantaneously. Atomicity is a guarantee of isolation from concurrent processes. Additionally, atomic operations commonly have a succeed-or-fail definition—they either successfully change the state of the system, or have no apparent effect.
Atomicity is commonly enforced by mutual exclusion, whether at the hardware level building on a cache coherency protocol, or the software level using semaphores or locks. Thus, an atomic operation does not actually occur instantaneously. The benefit comes from the appearance: the system behaves as if each operation occurred instantly, separated by pauses. Because of this, implementation details may be ignored by the user, except insofar as they affect performance. If an operation is not atomic, the user will also need to understand and cope with sporadic extraneous behaviour caused by interactions between concurrent operations, which by their nature are likely to be hard to reproduce and debug.
The remainder of this article focuses on the supply of goods.
A supply schedule is a table which shows how much one or more firms will be willing to supply at particular prices under the existing circumstances. Some of the more important factors affecting supply are the good's own price, the prices of related goods, production costs, technology and expectations of sellers.