BORIS Johnson's decision to prorogue the UK Parliament will come into effect tonight – but what exactly does that mean?

Well, in broad terms, it means a shambolic ceremony and a stark blow to scrutiny of the UK Government and the Prime Minister himself.

Tonight, the Commons will vote on whether to hold a General Election in October. It is expected that Johnson will lose this vote.

Later, Parliament will be prorogued until October 14, losing nine possible days it could have been sitting – with more possible during conference season, if MPs had voted as such.

This will be the longest prorogation of Parliament since 1945 – with court bids to block Johnson unsuccessful, though likely to be appealed.

For Johnson, this earlier-than-expected break-up of the Commons means he will be able to avoid what would have been his second Prime Minister's Questions.

It also means he can dodge his appearance before the Liaison Committee, which would see him questioned by the heads of select committees. This was scheduled for Wednesday, and would have lasted 90 minutes.

The earliest an election can now be held is November 21 – well after the current Brexit deadline of October 31.

A ceremony will take place after Parliament's business today. This will officially prorogue Parliament.

It will take place in the House of Lords, with the Leader of the House saying: "My Lords, it not being convenient for Her Majesty personally to be present here this day, she has been pleased to cause a Commission under the Great Seal to be prepared for proroguing this present Parliament."

The Commons will then be summoned. The Lords doff their hats, and the officials of the Commons bow.

Bills set to receive Royal Assent will then be given the Queen's approval. As each Act is read out, the Clerk of the Parliament will face MPs and declare "La Reyne le veult". This is Norman French for "The Queen wishes it".

A speech, written by the Government, will then be read on behalf of the Queen, reviewing the past year.

Any bills which have not received royal assent will fall through. 

If the Speaker grants two emergency debates requested today, this ceremony could take place after midnight.