Hanuman Jayanti celebrates the birth of Hanuman, the vanara god, on the 15th day of the shukla paksha during Chaitra. The festival is significant for Hindus, symbolizing strength and energy, with devotees performing rituals at temples to honor Hanumans devotion to Lord Rama. The celebration originated from a story involving a saint named Angira, leading to Hanuman's birth through divine circumstances, after which the vanara community and humans celebrate with joy and festivities.