http://livedocs.adobe.com/ Macromedia LiveDocs - online documentation with user feedback. Copyright 2009, Macromedia, Inc. 2009-11-25T13:14:48 en-us http://livedocs.adobe.com/specs/actionscript/3/as3_specification9.html#81021 FOr me the biggest advantage of interfaces is the ability to group class methods. <br /><br />Instead of testing every method for existence before using it, you just check to see if the class implements a certain interface that contains that method. If it does, you may use any of the methods in that interface without fear of it's non-existence. Then you can also set a behaviour to occur should the interface NOT be implemented. <br /><br />Thus you should get into the habit of grouping methods into interfaces and if you want a class to have those methods, extend the interface and implement all the appropriate methods. It may seem a pain if you only need one of the 5 methods but it will save you lots of time later like I said earlier, in testing every stinking method for existence before calling it. Joe@emeraldforest 0 0 2008-02-22T08:11:34 http://livedocs.adobe.com/specs/actionscript/3/as3_specification9.html#45783 Usually, you may use the interface type. Thus you can use any object of a class implementing the interface, even if it didn't exist when the variable definition was written. That's the main reason (polimorfism) of interfaces, not multiple inheritance. 0 0 2006-03-06T08:35:16 http://livedocs.adobe.com/specs/actionscript/3/as3_specification9.html#45691 You can use either the class or the interface as a type annotation because both represent data types. Francis Cheng 1 1 2006-03-02T10:36:20 http://livedocs.adobe.com/specs/actionscript/3/as3_specification9.html#45638 I'm still trying to understand the use of interfaces and then I saw this example and I'm more confused.<br /><br />should:<br />var greeter : Greetings = new Greeter()<br /><br />be:<br />var greeter : Greeter = new Greeter()<br /><br />and if not, why? 0 0 2006-03-01T05:55:34