I was surprised to hear from some developers that had not heard of Salesforce and the fact that there is an entire language called Apex that uses Salesforce as an operating system, and best of all, it's entirely free to use as an individual.
The cool part: This is where you live in the gray area that Salesforce sells as "No Software". What they really mean is "No Software To Install In Your Local Machine". For a developer, there is also no software to get started: you don't have to install an IDE (you can if you want to), you don't have to run a compiler, you don't have to install database drivers. You just login to your dev environment through Chrome, and you can start editing and running Java-like code and seeing it interact with your data, right away, using a query language that can call data or objects. The other good part is that there are vast amounts of free training available to you that enable to keep track of how much you're learning.