A class is generally associated to a business or functional logic. For example, you can combine all data and functions required for a worker to a class called as 'employee'. This might contain methods like AddEmployee, GetEmployeeDetails, CalculateSuperAnnuation etc. This would help you to create an object of Employee
MyObj = New Employee
MyObj.Name = "OneQuestion"
On the other hand, Modules can be used for generic functions like Filler function, declaring public variables etc
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