Actions 
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Functions 
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Action can contains Object Repository, Data table, Active screen etc.
   
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Function does not have these features. 
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Action can have multiple output(returning) values  
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Function can return only single value. 
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Action parameter type are byvalue only  
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VB script functions can be passed byref. 
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Action Parameter has default values  
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VB script function does not have any default values. 
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Action can/cannot be reusable  
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Functions are always reusable. 
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