Open source is this concept that ... Let’s say that you write me something that may be useful for my business. You have a number of options in terms of how you can give that to me. You could just sell it to me as something that I can’t change. That’s the typical proprietary approach. You just hand me something like this finished thing that my computer will run but then I don’t have any idea how you got to that.
The open source approach is a bit different. It’s the idea of releasing a tool or an application alongside the original code that actually creates that when you run it through a compiler on a computer or whatever other tool is applicable for that specific language. It essentially is distributed alongside a license that basically gives me the ability as an engineer to examine your code, to change it, to suggest changes and to contribute them back to you, and to really participate in the development of whatever it is you’ve built.