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copied!<p>Both types of objects more or less behave the same way, it is a matter of what they do that is the question. </p> <p>A delegate type object responds to actions that another object takes. For example, the <code>UITableViewDelegate</code> protocol has methods such as <code>didSelectRowAtIndexPath</code> for performing actions upon a user selecting a particular row in a table.</p> <p>Whereas a data source type object gives data to another object. For example again, the <code>UITableViewDataSource</code> protocol has methods such as <code>cellForRowAtIndexPath</code> and <code>numberOfRowsInSection</code> dictating what should be displayed in the table.</p> <p>There is no hard difference between the two in terms of compilation, it is simply a coding style to make what objects do what very clear to the user of the code.</p> <p>EDIT:</p> <p>To answer your second question: if you want each alert to respond differently, you will need to write a different delegate for each alert. For example, if one of your alerts is a save confirmation alert (perhaps you are going to overwrite a file, and it pops up to confirm thats what the user would like to do), you would have an object such as:</p> <pre><code>@interface SaveConfirmAlertDelegate : NSObject<UIAlertViewDelegate> @end </code></pre> <p>And in the <code>@implementation</code> for <code>SaveConfirmAlertDelegate</code> you would implement the proper save feature depending on which button the user pressed in the alert. </p> <p>When you create an alert view, you specify what the delegate object should be, this does not have to be <code>self</code>. You could have your four delegates stored as different objects and set them on the alerts as necessary.</p> <p>I hope this clears things up</p>

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