From the back of the book:
There are no limits!
GURPS, the Generic Universal Roleplaying System, is THE most flexible roleplaying system ever created. With just this Basic Set, you can adventure in any world you can imagine. Rules are included for all types of weapons from clubs to lasers ... for wizards and magic, with more than 100 spells ... for psionic powers.
No more switching game systems whenever you want to change campaigns! GURPS lets you learn one set of clear, comprehensive rules to cover any background.
And the GURPS system is fully support. Over 80 different worldbooks, sourcebooks and adventures are available for all kinds of campaigns.
GURPS makes the Game Master's job easy and fun. All rules are carefully organized, indexed and cross-referenced. Charts and tables are clear and legible. There's even a "Quick Start" section, with a solo adventure, to help you introduce new players to the system.
And the rules let you choose the level of complexity that you want.
GURPS is user-friendly for players, too. The character rules are detailed and flexible.
There are no "classes" or "levels". Instead, you can create exactly the character you want to play ... your favorite fictional hero, or your own original invention.
Choose from dozens or Advantages and Disadvantages, and over 130 Skills. Customize your character with some personal Quirks, and you're ready to play.