You can connect a wireless keyboard to a Mac or PC using Bluetooth, as long as the keyboard is charged and in pairing mode.

A USB receiver or connector (also known as a USB dongle) helps establish a wireless connection between your PC/laptop and the wireless keyboard to use within the supported range or distance. However, ...

You can connect a Magic Keyboard to your Mac through Bluetooth or using the Lightning port and charging cable.

While rooting around in my loft I came across an old ADB keyboard, it's an Apple Extended clone (By someone called Icicle according to the sticker on the bottom), this seams to be 'buck spring' board ...