P4 describe the features and functions of information systems

Features of information systems
Data	Data needs to be inputted into an information system so it can be managed and processed. Once processed the end product is information, this is the output. Data is generated by all departments and functions of a business but also received via external sources. Data must be accurate or else the output information will be wrong.
People	People are involved in obtaining data and processing it to create information for specific purposes relevant to the business. Staff need to have the correct training and skills to get the most out of information systems and make them effective employees.
Hardware	The hardware used in information systems must be capable of the software used in the business as well as handle the mass amount of data and information processed through it and stored on it. The hardware must be up to date to enable fast capture, storage and use of data.
Software	Software used by the business and its staff must have the correct features and functionality needed to produce and use information created by the business. It must also have the correct features to enable staff to correctly and efficiently do their job such as analysing and processing data and reports.
Telecommunications	Any output information produced will need to be shared around the business as it will be used for different purposes. Telecommunications need to be effective to ensure that data and information is transferred and distributed to the correct destinations after processing.
Functions of information systems	Information systems perform functions such as gathering input data, storing it, processing it and then producing output information. They also control this information flow as well as the feedback loop. There are also open and closed systems.
Input	Input with an information system has 2 different sections. Detailed data that is stored and processed creates the output. The user must specify to the system what sort of analysis they want the system to do.
Storage	Data should be stored at the most detailed level possible. IT departments may choose to store data of various summaries and should regularly backup data to avoid losing important data due to errors, these backups should also be stored in a geographically separate location to avoid a disaster (fire or flood etc…) affecting both the original data storage and the backup data storage.
Processing	This process is the function that transforms data into information.  Simple processing would be simply adding up the number of items sold by the business by a variable, such as the store location, the product or the time or date. Complex processing is the function of a computer performing calculations and making assumptions about any missing data to create the information from the data available.
Output	Output can be in 2 separate forms, graphical and textual. Graphical is often used to view information on a larger scale and presented as charts, graphs, diagrams and pictures. Textual is used to view the information on a smaller and more detailed scale, to do this it’s presented as charters, text or numbers.
Control and feedback loops	Control/Feedback loop is what happens to output once it has been processed and produced. The system repeats the same sequence depending on the output of the last loop, it has an effect on the input of the next data to information loop.
Closed and open systems	Information systems can be defined as open or closed systems, the difference being how they reacts and interacts to their environments. Open systems fully interact with its environment and can handle unexpected events because it monitors the environment, meaning it can adapt the output depending on circumstances. Closed systems are vastly separated and secluded from their environment meaning they don’t interact with it much. Any interaction will be planned and predicted beforehand or even as an automated process. It operates via triggers and acts according to events. They do not have an effect on external environments. An example of a closed system would be a payroll calculator that is automatic and is triggered by an event, such as payroll day.