Let's start with software, everyone knows what that is. Software is a computer program that does some kind of work. It could be word processing or spread sheets or computer games or anything else we covet at the local software retail store. They are exactly the same thing. What we are talking about here is price - how much it costs.
Software is traditionally pretty expensive although the price has been coming down over the years.
The programmer or software developer wants to be paid a fair price for his work output. Then we add in a competitive market with multiple software choices to perform the same thing and the price is set by what the market will pay. That still works today. There are new considerations today though. In other words, there are new motivations for writing new software.