Now that you have your system all up and working, you can access the operating system. The default operating system on the board is Debian, fortunately just the version you're interested in using. Linux, unlike Windows, or Android or iOS, is not tightly controlled by a single company. It is a group effort, mostly open source; it is available for free and grows and develops a bit more chaotically.
Thus, a number of distributions have emerged, each built on a similar kernel, or core set of capabilities. These core capabilities are all based on the Linux specification. However, they are packaged slightly differently, and developed, supported, and packaged by different organizations. Debian is one of these versions. This particular distribution is a popular one among DIYers, and it will allow you to use a number of different freeware software packages. Debian also has excellent support for new HW, and this can be very important for our projects.
So, you are going to use a version of Linux called Debian on your BeagleBone Blue. Once you are logged in to your BeagleBone Blue, you can issue some simple commands. If you type ls, you should see something like this:
The ls command simply lists the files and directories in the current directory. In this case, there is only one: the bin directory. In the next chapter, you'll learn more about the commands you'll need to access the Linux capability of the BeagleBone Blue as well as how to program the unit.