Peripheral is basically computer hardware. This hardware is installed onto a host computer in order to grow its abilities. Some of the devices that also form a part of this are externally hooked up are some form of computer bus, something like a USB. These examples comprise of include joysticks, printers and scanners. However, devices like monitors and disk drives which are not internal devices are not a part of the peripherals. Even video capture cards are not considered to be internal devices
Peripherals are the external devices which are connected to a computer eg: Keyboard , mouse , usb , joystick and etc...
I don't exactly know but it is something to do with computers
In medical terms: On the edges. I.e. Peripheral vision is what you see out of the corner of your eyes
Its means that. The outer peripheral of seeing around you looking out of your coner of your eyes