Gurpurbs are traditional Sikh holy days commemorating anniversaries related to the lives of the 10 Gurus.
The birthday, date of accession to the Guruship and date of martyrdom/passing are commemorated for each of the 10 Gurus every year.
Due to the fact that the Lunar Calendar is used to determine the dates, the dates of celebration vary each year. The SGPC (the chief management authority for the Golden Temple and Sikh Gurdwaras throughout India) shares the official Gurpurb calendar for the year ahead at the start of each Lunar New Year (typically the month of March on the Western calendar).
Baisakhi and Chhota Sahibzaday Divas are also considered Gurpurbs, and more will be shared about these occasions in the next lesson topics.