Now we know (more or less) what a device driver is, and how it can be easily implemented using the sysfs filesystem.

However, there exist tons of different device drivers for tons of computer peripherals, so starting from the next chapter, we'll see the most important computer peripherals available on the BeagleBone Black that an embedded developer may find in his/her professional life.

For each peripheral, we'll try to see how we can connect it to our BeagleBone Black, and how to configure and use the corresponding device driver by writing some example code. The next chapter talks about serial ports, which is one of the most important peripherals a computer can have.