Minimum System Requirements
Windows
OS:
Windows XP or better
Processor:
1 gHz
Memory:
512 MB RAM
Graphics:
OpenGL 2.1+ w/ GL_ARB_framebuffer_object
Storage:
300 MB available space
macOS
OS:
Snow Leopard 10.6.8
Processor:
1 gHz
Memory:
512 MB RAM
Graphics:
OpenGL 2.1+ w/ GL_ARB_framebuffer_object
Linux
OS:
glibc 2.15+, 32/64-bit
Processor:
1 gHz
Memory:
512 MB RAM
Graphics:
OpenGL 2.1+ w/ GL_ARB_framebuffer_object
Storage:
300 MB available space
Recommended System Requirements
Windows
OS:
Windows XP or better
Processor:
2 gHz
Memory:
1 GB RAM
Graphics:
OpenGL 3+
Storage:
300 MB available space
Notes:
Broadband Internet connection
macOS
OS:
Mavericks 10.9.2
Processor:
2 gHz
Memory:
1 GB RAM
Graphics:
OpenGL 3+
Storage:
300 MB available space
Notes:
Broadband Internet connection
Linux
OS:
glibc 2.15+, 32/64-bit, S3TC texture support
Processor:
2 gHz
Memory:
1 GB RAM
Graphics:
OpenGL 3+
Storage:
300 MB available space
Notes:
Broadband Internet connection
These are the requirements the publisher lists on Steam.