Can you give details of the functional units and basic operational concepts of a computer?

Functions of information systems:

Input - Input to an information system consists of two parts - There is the precise data which is stored and processed and forms the bases for the output from the system. Then the user must also inform the system of what sore of analyses require from the system. Sometimes this is unseen by the user and is set up by the it department in advance of users being in the system.

Storage - Data should be stored at the most precise and descriptive level possible. The department must also select to store different summaries of data for ease of use and consistency. The backups of data should be done frequently by the I.T department which should be held at various locations in case of issues that may arise.

Processing - The brief definition of processing is when data is turned into information at its simplest. At its hardest, calculations will be performed by a computer program, make estimates of missing information and select criteria to include or exclude.

Output - Graphical and textual are the two formats output can be in. Graphical consists of seeing the big picture, understanding trends and presenting to the management and is often best for it. Textual output is best for when you want accurate values and detailed work.

Control and feedback loops - A control and feedback loop is the outcome in the company's an result from the output from an information system. Some effects should occur on future inputs to the information system.

Closed and open systems - A in a closed system, there is a limited choice on what the users can report on. They are regularly straightforward and easy to use. The outputs are fixed in a closed system. An open system is where the user is more flexible on what to report on and the format in which the information is output. Major training may be needed before it can be used as it is really powerful.