20 years of Open Source

Before "Open Source" the name was "free software" (typically GPL)

A new name opened door for more collaboration in software development.

"Source" indicates compiled programming languages,
while source code of scripting languages is transferred in open by default.
"Open (source) code" could be more specific, but maybe more complicated name. 

"How I coined the term 'open source' | Opensource.com
Christine Peterson publishes her account of that fateful day, 20 years ago.
In a few days, on February 3, the 20th anniversary of the introduction of the term "open source software"

"We mean free as in freedom (free speech), not free as in beer."

Open-source software - Wikipedia