Classification of Functional Components

Once all the functional components have been identified they are classified into types depending on the type of activity they perform for the user.

Transactions can be classified into three types:

1. Inputs: enable the user to input data into the software to be stored

   e.g. Create Fault Record = Input

2. Outputs: enable the user to extract derived information from the software

   e.g. Aged Faults Report = Output

3. Enquiries: enable the user to query stored data

   e.g. Display Fault Details = Inquiry

Data Groups can be classified into two types:

1. Internal Files store data input by the user transactions

   e.g. Fault File = Internal File

2. External Files store data accessed by the user transactions but not maintained by the users’ transactions

   e.g. Account File = External File (where this file is maintained by another system)