Different countries have different legal systems.

With all systems go, the team was ready to launch the rocket.

There are several package management systems available for different programming languages.

The central nervous systems of mammals are responsible for coordinating and controlling bodily functions.

There are many content management systems available for website development.

Quadruple star systems are rare in the universe.

There are many binary star systems in our galaxy.

Trinary star systems are fascinating astronomical phenomena.

There are many single star systems in our galaxy.

Global positioning systems are used for navigation and tracking.