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.
In most flowcharts, the rectangle is the most common shape. It is used to show a process, task, action, or operation. It shows something that has to be done or an action that has to be taken. The text in the rectangle almost always includes a verb.