Which one of these is the most commonly used hardware interface for attaching peripherals to a microcomputer?

Hey there!

The most commonly used hardware interface for attaching peripherals to a microcomputer is the universal series bus, or USB, port. Many computers have at least 2 to 4 USB ports that allow for multiple devices to be plugged in at once. In terms of wired devices as opposed to wireless, this is the main way that a mouse, a keyboard, a smartphone (for charging and syncing information), and many other devices are connected to computers. 

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