Bruce Perens K6BP
Since a lot of people seem to be uninformed, here is some of what else is in the system besides Howard's great work. Lots of pieces are left out and this could be volumes long, and it highlights my own participation while there was equally notable work by others:
In the early 1980's Richard Stallman promoted the concept of Free Software and wrote the C/C++ compiler and Emacs editor we are using.
People at U.C. Berkeley wrote additions to the Unix system which we are using.
Many people joined in these efforts and contributed work we are using.
I published my first Open Source software, the Electric Fence malloc() debugger, commonly called "efence", from Pixar around 1987.
Guido von Rossum creates the Python language. I help Guido convince Bob Kahn at the Corporation for National Research Initiatives that he should allow Guido's work there to be free.
Linus Torvalds created the Linux kernel, a then-toy version of Unix, in 1991.
Ian Murdock created the Debian distribution of Linux in 1993, to be a free system.
I joined the Debian effort and was the second Debian project leader, and created the modern Linux distribution by distributing all of the core system devleopment to other developers worldwide, for the first time, before anyone knew that would work.
Eric Raymond and I created the Open Source Initiative in 1997. I was the first to announce Open Source to the world.
Nate Bargman and others develop Hamlib, the software we are using for radio control.
Eben Upton and friends at Broadcomm create the Raspberry Pi in 2006, and port Debian to it to create Raspbian.
The entire business world adopts Open Source because intellectual property is just too much of a hassle for software you aren't trying to make money from. It's better to just share it under an Open Source license.
Many, many more people contribute to the work on that SD card.