Saving feature in Unity5

Question

I'd like to know how to accomplish saving, accessing old save files, and overwriting them.

Answer 1

PlayerPrefs is a good place to start, but there are hundreds of ways to do this depending on what platforms, where you want to save, how often, etc.

https://docs.unity3d.com/ScriptReference/PlayerPrefs.html

It has limited space and a small set of data that can be saved (int, float, string), but it could be enough for a simple game.

If you need more space or more complex data structures to be saved, than you have to store them on the file system itself (or in a server if you have some backend support). Unity doesn't provide any built-in support for this.