Phlegm originates from the lungs. It is different from the mucus that is produced in the nasal passages. A common cause of phlegm is post nasal drip which is a symptom of sinus infections, colds, flu and inhalation of irritants. The diagnosis of the underlying condition could be made from the color of the phlegm.
A flow chart is a type of diagram representing a process using different symbols containing information about steps or a sequence of events. Each of these symbols is linked with arrows to illustrate the flow direction of the process.
One of the seven tools of quality, a flowchart shows how the entire system functions, and where error and wastes occur. This information is used in defining, documenting, studying, and improving the system. Also called flow diagram, flow process chart, or network diagram.