Learn object-oriented programming by building one program, a parking lot, in five steps. Every step has the full Java and C# code, a practice task and its solution.
Five deep dives that build one Parking Lot program, from the first class to the finished system: classes, objects and constructors; encapsulation, this and static; inheritance; polymorphism, abstraction and interfaces; and composition.
Each part has the code from the video in Java and C#, with its real output, a practice task with a starter project, and the solution (try it first). Every part also comes as a zip with the lesson code, the practice starter and the solution, for both languages.
Work through the parts in order: each one builds on the previous one.