SPECIAL

SPECIAL is the ruleset that powers all Fallout games. The name "SPECIAL" is an acronym standing for the primary statistics in the system: Strength, Perception, Endurance, Charisma, Intelligence, Agility and Luck.

Systems
Characters in SPECIAL are defined through:
 * Primary statistics
 * Derived statistics
 * Skills
 * Perks
 * Traits

Fallout 3

 * In Fallout 3, if Broken Steel is installed and the Almost Perfect perk is taken prior to collecting any SPECIAL bobbleheads, they can then be collected to get 10 in all SPECIAL stats.
 * As in Fallout 3, there is a copy of the You're SPECIAL! book in Fallout 4. It can be found in Shaun's room in the ruins of the Sole Survivor's home in Sanctuary Hills. Using it allows you to permanently boost one SPECIAL by one.

Fallout 4
In Fallout 4, it is possible to permanently get 11 in all SPECIAL stats by having 10 in all SPECIAL stats through character creation or spending perk points, and then using the respective bobbleheads.

Fallout 76
In Fallout 76, the player character gains a SPECIAL point to spend every level, until level 50, and it is possible to get up to 15 in each stat.

Behind the scenes

 * Initially, Fallout was meant to use the GURPS system by Steve Jackson Games. However, there were difficulties in the license that could not be overcome, and so the two companies mutually agreed to end the partnership. Chris Taylor, Jesse Heinig and Tim Cain developed the SPECIAL system instead. Jason G. Suinn was responsible for pointing out that the acronym of statistics spelled "SPECIAL" as opposed to Cain's working acronym "ACELIPS."
 * Two other projects use the SPECIAL system, including Lionheart: Legacy of the Crusader and TORN.