A is used before consonants, an before a vowel sound. A comes before words that begin with a u, but are pronounced as though they began with a y: a union; a useful gadget. An comes before a silent h: an heir; an honour. Some people still use an before h in words from French, where the h was silent: an hotel. This is rather old-fashioned. There is no reason to use an before an h which is sounded.
The Union Jack signifies the islands' wish to preserve links with Britain. The nine stars representing the islands are placed according to their locations. Effective date: 11 April 1997.