To create context diagrams, the external factors affecting the flow of the data must be the key focus of the diagram. Context diagrams are a type of data flow diagram identifying external factors and how they are related to the process or system in a graphical representation. This type of diagram is often used by system engineers and architects as a tool to design systems that process information. A context diagram is developed using the flowcharting symbols readily available in most word processing and graphics software packages.
Click "Start," "All Programs," "Microsoft Office," "Microsoft Word" or open any word processing software with flowchart symbols.
Click "Insert" and then "Shapes" or display your "Drawing" tool bar to make your shapes readily available for selection.
Using the drawing tools or the "Insert" menu to place "Shapes," draw or insert a rectangle in the centre of the page.
Draw a second rectangle on top of this one with the same width but only one-quarter of the length of the first rectangle.
Right-click to "Add Text" or use the drawing text tools to label this box. This box represents the essential data flow and processing that is affected by external factors. For example, this box might represent the Payroll Processing system receiving payroll input from a variety of external sources.
Add the external data flows for this process around the central rectangular processing box using the drawing tool. You can also "Insert" a "Picture," "Clip Art" or whatever graphic symbols you need to represent the people, banks and other businesses that provide key inputs to the Payroll Processing system.
Connect each symbol, person, bank and business to the central rectangular process representing the Payroll Processing system. The connectors can be lines with or without arrows as long as they accurately represent the flow of data in the context diagram.