Today, February 6, Queen Elizabeth II is celebrating 70 years on the throne.

The Queen is the first British monarch in history to celebrate her Platinum Jubilee.

Elizabeth II will have reigned for 70 years, or 25,568 days, on Sunday, February 6, excluding this Accession Day itself.

The Queen paid tribute to the Duke of Edinburgh, the Queen Mother and the Duchess of Cornwall in a message celebrating the role of consorts in the royal family, as she set out Camilla’s future title as Queen.

What is a royal consort?

A royal consort refers to the spouse of a serving monarch. Their main duty is to provide support and companionship during their reign.

Unlike the king or queen, they do not have a formal position or set tasks and responsibilities.

READ MORE: The Queen's Platinum Jubilee message in full

Throughout history, however, those in the role have held considerable influence. This was evident through Prince Albert when he served as Prince Consort to Queen Victoria.

Consorts traditionally help the king or queen in their programme of public engagements, from hosting heads of state to attending charity galas.

Queen Consort

The Queen Mother was King George VI’s consort and the first British-born Queen Consort since Tudor times.

Her position as consort saw her visit Commonwealth nations and undertake major tours alongside her husband.

After the king’s death, the Queen Mother continued public duties for many decades and remained patron of about 350 organisations.

Philip automatically became Elizabeth II’s consort when she acceded to the throne in 1952.

He made history when he passed the record as Britain’s longest serving consort in 2009.

In 1953, Philip was the first layman to pay his respects to the Queen on her Coronation Day, immediately after the archbishops and bishops.

The duke dedicated decades of his life to public duty.

Unlike Philip, who declined the title of prince consort, Prince Albert was officially given the formal title in 1857.

Camilla to be Queen Consort

In her Jubilee statement, the Queen paved the way for Camilla to be known as Queen Camilla.

As the Prince of Wales’s spouse, she was already automatically set to be his consort and also technically queen when he becomes king.

However, Royal aides said at the time of her wedding in 2005 that she would be known instead as Princess Consort.

The Queen said in her Platinum Jubilee message on Saturday: “When, in the fullness of time, my son Charles becomes King, I know you will give him and his wife Camilla the same support that you have given me, and it is my sincere wish that, when that time comes, Camilla will be known as Queen Consort as she continues her own loyal service.”

The wife of a king, known as a queen consort, is crowned at a coronation ceremony, unlike the husband of a queen.