What does a classe Manager?

As mentioned in my earlier post, I am not much of a "theory" person and avoid engaging in debatable issues. People use different terms to mean different things and there are no fixed meanings to attached to some words.

I am also not much of "Patterns and Practices" person either.

Coming back to your post, I don't personally believe that it can be called CustomerRepository because the class itself doesn't store anything. It only "helps" store the data. The real repository of data is the database table.

Let me give you a piece of unasked advice. Do not ever pay too much attention to such terminologies, In my strictly personal opinion these are meaningless and plain distraction. Many people give too much importance to this and loose the focus on the real meat of the stuff.

To put it simply, CustomerManager class it the class which is responsible for entire customer management in the application. There will be a class called CustomerModel which will hold the customer data (properties), such as Id, Name, etc.

Now this CustomerManager class is responsible for saving CustomerModel to a persistent data storage (i.e. database), retrieve CustomerModel (single or multiple), delete / update customer data, etc.

Now you tell me what great philosophy is there behind the word "Manager"?

Please take a look at below link. It is good to start with.

https://msdn.microsoft.com/en-us/library/system.configuration.configurationmanager(v=vs.110).aspx

these manager files/classes are basically kind of driving the entire application management with some global data stored in it.