Cough

The cough is a sudden and often repetitively occurring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles and microbes. The cough reflex consists of three phases:
• An inhalation
• A forced exhalation against a closed glottis
• A violent release of air from the lungs following the opening of the glottis, usually accompanied by a distinctive sound.
Cough can be either voluntary or involuntary. Frequent coughing usually indicates the presence of a disease. Coughing can be due to respiratory tract infection and can also be triggered by:
• Choking
• Smoking
• Air pollution
• Asthma
• Gastro esophageal reflux disease(GERD)
• Post-nasal drip
• Chronic bronchitis
• lung tumors
• Heart failure and medications such as ACE inhibitors.

https://www.medylife.com/blog/health/cold-and-cough-causes-symptoms-treatment-and-home-remedies/
Types:
• Acute cough: It begins suddenly and can be caused due to sinus, flu or sinus infection.
• Sub acute cough: It lasts for 3-8 weeks
• Chronic Cough: It lasts longer than 8 weeks.