The Queen's Speech at the State Opening of Parliament explained

The Queen is expected to announce major reforms to Britain's prison system at the State Opening of Parliament today.

The speech is steeped in centuries of tradition. Here is what you need to know.

• What is the State Opening of Parliament?

The State Opening of Parliament marks the start of the Parliamentary year - and has been carried out for the past 500 years.

It is held in the House of Lords.

It used to take place in the autumn each year, but since 2010 it is usually scheduled for May thanks to the introduction of five-year fixed-term parliaments.

Before the Queen travels to Parliament from Buckingham Palace, certain historical "precautions" are observed, such as a search of the Palace of Westminster's cellars - a practice which dates back to the Gunpowder Plot in 1605.

• What is the Queen's Speech?

The Queen gives a speech at the State Opening of Parliament setting out the policies the Government plans to implement over the next Parliamentary session.

The speech is written by the Government, not the Queen.

She will make her way to Westminster in a horse-drawn state coach, accompanied by the Duke of Edinburgh.

On arrival, the Queen puts on the Imperial State Crown and her parliamentary robe ready for the ceremony itself in the House of Lords.

The final words after delivering the speech, "other measures will be laid before you", give the Government flexibility to introduce other legislation as necessary.

The Queen has opened Parliament on all but two occasions throughout her reign. These were 1959 and 1963, when she was pregnant with Prince Andrew and Prince Edward.

• What is likely to be in the Queen's speech this year?

The most radical reforms to Britain's prisons since Victorian times are expected to feature, along with the repealing of the Human Rights Act.

More details on what could be included in the Queen's speech today can be found here.