The primary cultural festival celebrated in India that symbolizes the victory of light over darkness is Diwali, also known as the Festival of Lights. This Hindu festival is celebrated annually, typically in October or November, and is marked by the lighting of oil lamps, bursting of fireworks, and decorating homes with colorful rangoli. Diwali signifies the triumph of good over evil and knowledge over ignorance, commemorating various historical and mythological events, including the return of Lord Rama to Ayodhya after defeating the demon king Ravana. Families gather to perform prayers, share sweets, and spend time together, fostering joy and unity.