What can a peripheral device plug into

It could be a usb or a vga port if it were a monitor

A peripheral device is a device that receives input or gives out output.

Input devices will include the devices as followed:

1. Keyboard

2. Mouse

3. Touchpad

Output devices will include the devices as followed:

1. Monitor

2. Speakers

3. Printer

Each device connects in a different way but in modern times recently, most devices use USB plug in ports but some peripherals use other plug in ports such as Firewire which is probably the second most used port after USB ports.