Holy Thursday, also known as Maundy Thursday, Covenant Thursday, Great and Holy Thursday, Sheer Thursday and Thursday of Mysteries.
Holy Thursday commemorates Jesus washing the feet of his disciples (Maundy) and the Passover (Last) Supper he took with the disciples. It is also the start of the Easter Triduum (the three days of Holy Thursday, Good Friday and Holy Saturday), the three days which celebrate the last days of Christ and His ultimate sacrifice for us and the whole world.