Swine Flu, also known as H1N1 influenza, is a respiratory illness caused by a virus that primarily affects pigs but can also infect humans. It was first identified in 2009 and led to a global pandemic. Symptoms in humans are similar to those of regular flu, including fever, cough, and body aches. The virus spreads through respiratory droplets when an infected person coughs or sneezes. Vaccines are available to help prevent infection, and antiviral medications can treat those who become ill. Public health measures, such as handwashing and avoiding close contact with sick individuals, are also important in controlling its spread.