Question

For example

Public int Width
{
    get { return Something.Width; }
}

instead of

Public int Width;
//later in the code
Width = Something.Width;

or

Public int Width = Something.Width;

Answer 1

1) Width is just a question you can ask about an object, how wide are you? Outside you don’t really care how width is dealt with inside, you just care about what is the answer.

2) Width may change, right now it’s just a width member variable but later maybe it’s a calculation or maybe the object is really a list of other objects. The object itself should be responsible for all that and not someone outside who is not-the-object.

3) The less outside objects know about how and the more they only care about what the easier it is to understand code you or someone else wrote a year ago.

4) It centralizes control over the width property of that class which means that code is all in one place and easy to maintain. Any other way if something changed then code all over your program has to change, too, and that’s just a big mess 😉

5) The same goes with using setters instead of just shoving a number into Something.Width directly.

So basically it’s a way of keeping the inside world of an object safe from the outside and making it really easy to change how an object works without disturbing the rest of your program.