Australia Celebrates Queens Birthday

1. The birthday of Queen Elizabeth II is a public holiday in Australia.
2. The Queen's birthday is celebrated every second monday in June each year.
3. The real date of the Queen's birthday is 21 April 1926.
4. The Queens birthday is celebrated by Australians in June to avoid coinciding with Easter celebration which is usually celebrated on 21st of April and positioned very close to Anzac Day which is celebrated every 25th of April commemorating the members of the Australian and New Zealand Army Corps (ANZAC) who fought at Gallipoli in the Ottoman Empire during World War I.
5. Queen Elizabeth II was born Elizabeth Alexandra Mary of the House of Windsor.
6. Queen Elizabeth II was the first child of King George VI (formerly Prince Albert, Duke of York) and Queen Elizabeth (formerly Lady Elizabeth Bowes-Lyon, Duchess of York).
7. 1977 marked the Silver Jubilee, 2002 marked the Golden Jubilee, and 2012 marked the Diamond Jubilee of the reign of Queen Elizabeth II.
8. Queen Elizabeth II was crowned at Westminster Abbey on 2 June 1953 at the age of 25 and her coronation was broadcast on TV for the first time. She became Queen when King George VI died on 6 February 1952 while Princess Elizabeth and Prince Philip were touring Kenya.
9. Queen Elizabeth II's accession made her Head of the Commonwealth and queen regnant [3] the Commonwealth Realm.[1]
10. Queen Elizabeth II is married to Prince Philip, Duke of Edinburgh and has four children and eight grandchildren.
11. Queen Elizabeth II is the second-longest-serving current head of state after King Bhumibol Adulyadej of Thailand.
12. Queen Elizabeth II is the longest-lived and second-longest-reigning British monarch.[2] (Queen Victoria, her great-great grandmother, reigned longer).

Terminologies From Wikipedia:

[1] Commonwealth Realm - A Commonwealth Realm is a country which has The Queen as its Monarch. There are 15 Commonwealth Realms in addition to the UK: Australia, New Zealand, Canada, Jamaica, Antigua and Barbuda, Belize, Papua New Guinea, St Christopher and Nevis, St Vincent and the Grenadines, Tuvalu, Barbados, Grenada, Solomon Islands, St Lucia and The Bahamas.
[2] Monarch - A monarch is the sovereign head of a state, officially outranking all other individuals in the realm. A monarch may exercise the most and highest authority in the state or others may wield that power on behalf of the monarch. Typically a monarch either personally inherits the lawful right to exercise the state's sovereign rights (often referred to as the throne or the crown) or is selected by an established process from a family or cohort eligible to provide the nation's monarch. Alternatively, an individual may become monarch by conquest, acclamation or a combination of means. A monarch usually reigns for life or until abdication. Monarchs' actual powers vary from one monarchy to another and in different eras; on one extreme, they may be autocrats (absolute monarchy) wielding genuine sovereignty; on the other they may be ceremonial heads of state who exercise little or no power or only reserve powers, with actual authority vested in a parliament or other body (constitutional monarchy).

[3] Queen Regnant - (plural: queens regnant) is a female monarch who reigns in her own right, in contrast to a queen consort, who is the wife of a reigning king, or a queen regent, who is the guardian of a child monarch reigning temporarily in their stead.

References:

Monarch
Queen regnant
Constitutional monarchy
Elizabeth II
Anzac Day
More information about: The Queen
Home - Her Majesty The Queen
Anzac Day 2015
Queens Birthday