What is the difference between Micro A and Micro B?

What is the difference between Micro A and Micro B?

Type A plugs are typically used to plug into a “master” device, such as a computer. Type B plugs connect to a “slave” device, such as a printer or cell phone.

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A micro-B receptacle will only work with a micro-B plug. A micro-AB receptacle will work with both micro-A and micro-B plugs.