I have a background in Fortran, but lately I've been studying C# so that I can understand some of the things that my grandson is doing in his programming. My background has helped me get through many of the beginning concepts, and I've written some decent programs to solve some physics forums problems. But, the concept of object oriented language is new to me, and I'm struggling to get an understanding of Classes, and working with Classes. I've looked over many online references, and have gotten some understanding, but I'm still struggling. Any recommendations on good (and simple, straightforward) sources would be greatly appreciated. Thanks.
Chet