Influenza is a common, contagious respiratory illness caused by influenza viruses. It spreads primarily through airborne droplets generated when infected individuals cough or sneeze, or through contact with contaminated surfaces. Symptoms commonly include fever, cough, sore throat, body aches, and fatigue. While most cases are mild, the illness can lead to serious complications, especially in vulnerable populations. Management focuses on supportive care, and preventative measures include vaccination and rigorous hygiene practices. Antiviral agents are utilized in severe cases to limit viral replication and alleviate symptoms.