Dharmaraja Dashami or Yama Dharmaraja Dashami is dedicated to Lord Yama, who is the Hindu God of death. Dharmaraja Dashami 2024 date is April 18. A puja dedicated to Yama who is also known as Yamadharmaraju is held on the day. This Vrata is observed on 10th day during the Shukla Paksha of Chaitra month.
Basically the pujas that are performed on the day concentrates on removing the fear of death from a devotee.
It would be nice to note hear the story of young Nachiketas in the Katha Upanishad who went to the abode of Yama to learn about the secret of death.