What is meant by 'commercial code'? I have never heard this term before. I have never written code and sold it. I have written a lot of code which is part of b

What is meant by 'commercial code'? I have never heard this term before. I have never written code and sold it. I have written a lot of code which is part of business process, and no doubt still running. Do I count the code I wrote for my friend's BBS in 1993? That might be the first code I wrote which was useful to someone else. Or should I count the first code I wrote that someone paid me to write? That would be much later in 1999. Or should I count the code I wrote to help me run my own business in 1997? Is it possible for an open source developer to never write any commercial code? Has Richard Stallman ever written commercial code?