Black Friday began in USA and is the biggest one day retail event of the year. It is held the day after Thanksgiving and is the lead up to the 'holiday' season, we call it Christmas.

It is not catching on in a number of other western countries, here in Oz we are now having our second year of it running from Friday into Sunday. But of course being in the southern hemosphere our days are much longer than yours in the North and that is why it goes for three.