Question: How do you make a USB key

Ted Burke answered on 9 Mar 2019:

The main component inside a USB key is flash memory – this is a type of microchip that stores data in the form of billions of 1s and 0s. Unlike the electronic memory of most computers, flash memory doesn’t lose the information that’s stored in it when the power is switched off, so a USB key keeps the files stored on it safe when it’s plugged out. The second most important component in a USB key is some kind of “microcontroller” – this is a tiny computer (all inside a single microchip) that runs some software to manage transfer of data to and from the PC when it’s plugged in and also to manage storage and retrieval of data in the flash memory. Apart from that, there would be a few other components like a crystal oscillator to set the clock speed that the microcontroller runs at and the physical USB plug that you insert into the socket on your laptop or PC.