First started by US based Hallmark cards founder, Joyce Hall in August 1930 to promote greeting cards.
The idea of World Friendship Day originated in Porto Pinasco, Paraguay on 30th July, 1958, this day is accepted by UN. Many South American countries celebrate it on this day.
In US & South Asian like India, it is celebrated on the 1st Sunday of August.
Nani Annan, wife of UN secretary general Kofi Annan declared Winnie the Pooh as the global ambassador of friendship in 1998 at the UN.
Friendship band, cards & flowers are exchanged during this day. Members of group write positive, hilarious messages on the shirt/T-shirt of other members.
A game invisible friend is a tradition of this day, where members of a friend's group pick a name from sheets of paper & gift the person on friendship day.
In India, concept of friendship dates back to the era of Krishna-Sudama.