From the back cover:
2300AD games range from interstellar exploration and interstellar war, down to the gritty streets and the mega-cities of the human core. This is a game about people, and their rise to the stars. Aliens are a part of the 2300AD milieu, but the focus of the game is on humans.
Explore the sights and mysteries of the French Arm, one of humanity's main thrusts into the depths of space. This book contains several adventures set in the French Arm, allowing you to kick start a 2300AD campaign quickly and with the minimum of fuss.
The Traveller Core Rulebook is required to play 2300AD.