Red spine included just the OS/2 Warp without Window 3.1 (although you can add it with a copy of Windows 3.1.) The Blue spine came with Windows 3.1.
OS/2 Warp 3.0

Red spine included just the OS/2 Warp without Window 3.1 (although you can add it with a copy of Windows 3.1.) The Blue spine came with Windows 3.1.
The first client based user operating system to include SMP support.