Science

Science is a Fallout, Fallout 2, Fallout Tactics, and Fallout 3 skill.

Covers a variety of hi-technology skills, such as computers, biology, physics and geology.

Fallout, Fallout 2 and Fallout Tactics
Initial Level: Starting Science skill is equal to 25% + (2% x Intelligence). This formula would mean average characters will have a 35% Science skill (25% + (2 x 5)), with the minimum value being 27% and the maximum 45%.

The Fallout Tactics 1.27 patch notes readme file says:"The science bonus to criticals on robots is working properly"suggesting that Science affects critical chance or effect against robots somehow (at least in Tactics).

Fallout 3
Science allows you to hack terminals using the mini-game described in Hacking Terminals. Terminals have different difficulty levels, and they require different science skill levels. The difficulty ratings and skill levels are: Very Easy (15), Easy (25), Average (50), Hard (75), and Very Hard (100). This is one of the few skills that may be useful to find a way to raise it to 100% (like Lockpick) as some terminals require such a high level. The relative values of your science level and the difficulty rating affects how hard the minigame is. Harder terminals have more words, longer words, and fewer brackets for removing duds.

This particular skill is able to be raised by the science-oriented book, the Big Book of Science.

Science is also what determines the probability that you will succeed in disarming a slave collar.