H1N1, also known as swine flu, is a strain of influenza that emerged in 2009 and caused a global pandemic. The virus is a combination of genetic elements from human, avian, and swine influenza viruses. It spreads through coughing and sneezing and causes symptoms like cough, fever, fatigue and sore throat. While most people recover without treatment, those at higher risk for severe illness include pregnant women, children, and people with chronic health conditions. Prevention strategies include vaccination, hand washing, and maintaining a healthy immune system through nutrition, lifestyle factors and herbal remedies.