Good Friday falls on the Friday before Easter Sunday in New Zealand. The day commemorates the crucifixion of Jesus Christ.
Celebration\ Observance
Catholics may fast, or not eat meat, or have small meals as part of the day. For many in New Zealand it will be the start of their 4 day weekend that includes Easter Monday.
History
For Christians this day is important as a day of mourning for the crucifixion of Jesus Christ and the resurrection to follow on Easter.