Comprehension

Comprehension is a Fallout 2, Fallout Tactics, J.E. Sawyer's Fallout Role-Playing Game, Fallout 3, and Fallout: New Vegas perk.

Fallout 2 and Fallout Tactics
Yes, reading can be fun. You receive twice as many skill points when reading books.

Fallout 3
You gain one additional skill point whenever a skill book is read. However, points gained from books before selecting this perk are not doubled.