Programs in Information Systems
In information systems, the central role of programs is to process information. A set of inputs are processed into a desired set of outputs. This is the input-process-output model. Inputs are anything provided to the system. Outputs are what the user gets back from the system. The process in between is all of the work done by the computer.
As an example, think of a web form to send feedback to a company. The personal information and comment entered into the form is the inputs. One output is the form being sent to the company as an e-mail. Another output is the message to the sender indicating the form was submitted properly. In between the inputs and outputs, the program has to process the information. At the very least, it has to put all the information together and send it to the company. It may also check that all required information has been entered, verify a customer number, ensure data like phone number or zip code has been entered correctly, check communications, or perform other, similar process tasks. The processes are effectively what happens behind the scenes.
A simpler example would be a calculator interface. A use might type in 3+5 as the input. Then, 8 will appear on the screen as the output. In between, the process requires interpreting the equation entered, calculating the result, and sending the information to display.
Most information systems include many such input-output relationships and rely on programs to process from inputs to outputs. The input-process-output model for programs facilitates situating the program within the information system and communicating the relationships.
Based on your understanding of what a program does in terms of processing inputs to outputs, describe an overall information system you have worked with at home, work, or school and consider the program or programs at the core of that information system. Identify several examples in that information system in which a user inputs specific information or triggers a specific event. What are the expected outputs for each user action? Describe the process that must occur in between the inputs and outputs.