A USB port is the type of port that is used by an infrared mouse. This type of mouse does not require batteries and uses infrared light in order to operate.
PS/2 (For Keyboard and Mouse)USBCOM1 and COM2 (serial) PortParallel Port (for Printers)SpeakerMicVideo Port (Monitor Port)Lan Port
Infrared or IRDA port is a wireless serial port which uses Infrared (invisible) light for transmission and reception of data. (Infrared light is also used in TV remote controls). Infrared port on a laptop computer can be used to transfer data to and from another computer or a mobile device like a PDA or mobile phone without wires over short distance. Infrared port will need a line of sight communication path i.e. to establish a connection and for reliable communication Infrared ports of two devices should face each other. Not all laptops have Infrared ports. Some have these built in the machine and for some if needed you will have to add an Infrared port device on USB port. - Neeraj Sharma
The USB port, unless it is a Bluetooth mouse, then there is no port, it will connect via Bluetooth.
A wireless mouse requires (typically) a USB port for the receiver. As long as your computer has an open USB port and the drivers to support the device, it doesn't matter what type of keyboard is attached to your computer.
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I haven't seen a router with infrared port, even if you have one you will not able to use internet because the protocol which is being used by infrared does not support internet calls.
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Yes you can. Just make sure the new mouse can plug into the usb or mouse port of your computer.
You have a mouse. You used it to get here. Oh, and by the way its USB
Infrared port is used to transfer data through a ray of infrared light. Two ports must be in close distance and pointing to each other in order to transfer anything. This method is very slow though, it has been used mostly with old cellphones and laptops.
USB Port
USB Port