Bluetooth is a short range wireless technology which connects devices and peripherals.
Bluetooth was named for Norse King Harald Bluetooth who united tribes together. Bluetooth provides a single common technology to unite various devices and peripherals. It can also connect two computers together.
Bluetooth wirelessly connects mouse, headphones, speakers, keyboards, and so on to different computers, such as desktops, laptops, tablets, cell phones, and the like.
It works by first setting up the computer device to which you will be connecting a peripheral as follows. In Settings you put the device into bluetooth search mode. You may also need to make visible to other devices.
The next is tricky. The peripheral you are connecting then needs to be paired. The process is unique to every device. The peripheral is put into pairing mode.
The peripheral you are connecting comes with instructions. You need to be sure to turn that device on. Then typically you need to tap and hold a pairing button on it, or more than one button. That may take as long as 30 seconds or more. Be patient. There may be a flashing light to show that it is in pairing mode.
Finally, if all goes well, the computer device to which you are connecting the peripheral displays a name for the peripheral.
That computer device may also ask for a pairing code and usually 0000 or 1234 will suffice. If not the instructions for the peripheral device you are connecting will provide another code.
Once the devices are paired, they should automatically connect later.