Computer hardware connectors. View of several different types of connectors and cables used with personal computers. The largest connectors (at left and lower right) are SCSI or small computer system interface. These are used to plug in peripheral devices such as hard disk drives, CD- ROM drives, laser printers or scanners. The medium sized are video connectors (upper right and lower left) which are used to plug in video monitors. The smallest two cables are ETHERNET connectors for connecting networks of different computer users.