The festival fifty days after Easter (originally 50 days after Passover). When the Holy Spirit descended on the apostles, and they became brave, couragous, and more outgoing generally. Also, taken by most to be the birthday of the church, or of Christianity.
Food: birthday cake, anything flame-grilled, etc.
Decorations: white, doves, flames, candles, etc.
Muisc: venati, creator spiritus, veni, sancte spiritus, Come down O love divine, etc.
Hooray for: speaking foriegn languages, flames, being brave, interacting with people.