A confectionary common in Australia and New Zealand. Orange flavoured (hence the name), they consist of a small chocolate sphere covered with a red-orange candy shell.
Traditionally sold in movie theatre concession stands, they fill a similar sweet ecological niche to Junior Mints or Milk Duds. They're known nostalgically to old folks for making a enormous noise when spilled down the wooden stairs of cinemas.
'Jaffa' has also come to describe the flavour combination of orange and chocolate - Jaffa cake is a good example.