What is the difference between public, private, and protected?

Question

You use:

public scope to make that property/method available from anywhere, other classes and instances of the object.
private scope when you want your property/method to be visible in its own class only.
protected scope when you want to make your property/method visible in all classes that extend current class including the parent class.

If you don’t use any visibility modifier, the property / method will be public.

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