8" floppy disks

8 inch floppy disks were first popular floppy disks. They were used in nearly all aspects of computing in 1970s and early 80s.

These floppy disks were used in computers, workstations, microcomputers, industrial analysers and machine driving computers, and even in some terminals.

Manufacturer: different

Type: Disks
Capacity:  80kB-500kB, some had 980-1200kB.

     If you want to plug 8" drive to a PC?
By hardware - it's possible. Most 8" drives stick more or less to Shugart floppy disk standard, so it's electrically similar to PC, but cabling is different. CP/M FAQ shows how to build adapter for most popular drives. For old, especially eastern block drives this adapter must be different, as they usually use different pinouts.

The problem comes with software. Disks are different. There are many CP/M formats, add industrial analyser/driving computer formats, mainframe formats, custom workstation formats... probably few hundred if not thousands. These formats use different sectoring (hard/soft, soft - how?), tracks, sides, steps, speeds, modulations, geometries etc. Not all supported by PC electronics. There is some documentation on other websites which may give some clues.
If you have CP/M disks, you can try to move files to 5.25" disk, and then read it in PC similar way to Robotron 1715 disks. This may work if 5.25" format can be understood by PC. Some CP/M disks are raw-readable using Linux dd, but in most cases it's not a reliable way.