Influenza, commonly known as the flu, is one of the most widespread viral diseases in the world. It is a contagious respiratory infection caused by influenza viruses, which are classified mainly into three types: A, B, and C. The severity of symptoms varies depending on the virus type and the health condition of the infected person. The flu spreads through droplets released when an infected person coughs, sneezes, or talks. It can also be transmitted by touching contaminated surfaces and then touching the nose or mouth. Symptoms usually appear within two to three days after infection and include high fever, severe headache, muscle and joint pain, nasal congestion, sore throat, persistent dry cough, fatigue, and loss of appetite. Most people recover within five to seven days, but some groups — such as children, the elderly, and people with chronic illnesses like asthma or diabetes — may develop serious complications such as pneumonia or sinus infections. To prevent influenza, doctors recommend getting the annual flu vaccine, which helps the body build immunity against circulating virus strains. Maintaining personal hygiene, washing hands regularly, avoiding close contact with infected individuals, and following a healthy diet rich in vitamins can also strengthen the immune system. Influenza serves as a clear reminder of the importance of health awareness and prevention. Although it may seem mild in most cases, neglecting it can lead to serious illness. Therefore, vaccination and hygiene remain the best ways to protect oneself and the community. Al _ Mustaqbal University, the first university in Iraq