Connecting external devices to my iMac

Your tag line says that you have a 24" iMac running macOS 15.1 (Sequoia). That suggests that it is a 24" M1, M3, or M4 iMac.

The USB-C port mix will depend on which specific iMac you have. There may be:

• Two multi-purpose ports (marked with lightning bolt symbols)
• Two multi-purpose ports (marked with lightning bolt symbols), plus two USB-only ports
• Four multi-purpose ports (marked with lightning bolt symbols)

Apple calls the multi-purpose ports "Thunderbolt / USB4" ports. Like the unmarked ports, they support traditional USB. But they also support:

• Thunderbolt 3 or 4 (up to 40 Gb/s)
• USB4 (up to 40 Gb/s)
• DisplayPort

This makes them suitable for connecting docks, displays, and high-end external SSDs. You can use them as "plain" USB ports, and there' nothing wrong with that, but if you need the higher-end stuff, it's there.

Your iMac is also equipped with Wi-Fi and Bluetooth, and may be equipped with an Ethernet port (that would allow a wired network connection to your router). Finally, there is a headphone jack on the side.

What kind of external device? What connection or cable does it use?

Provide some details about the device , and someone may be able to provide specific advice.

You may be referring to older USB A and USB B devices. If that is what you are referring to please get some adapters such as the USB to USB C adapter which are quite in-expensive!

Sure. There are many ways, but there are many devices too. It would help if you were to provide some additional details:

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