So, what does it mean and what happens next?
Q. What does prorogation mean?
A. Prorogation marks the end of a parliamentary session.
Q. Who does it?
A. The Queen prorogues Parliament following guidance from the Privy Council.
Q. Why does Boris Johnson want to prorogue Parliament now?
A. A new Government brings with it new plans and legislation which are set out in a Queen's Speech. Mr Johnson insists he asked the Queen to end the current session of Parliament so he can start anew.
Q. What happens during prorogation?
A. MPs and peers cannot formally debate policy and legislation or make any laws of their own. The powers of the Houses of Commons and Lords are taken away until the next Queen's Speech.
Q. How long will Parliament be prorogued for?
A. Prorogation normally tends to be for a short amount of time - no longer than two weeks, with it leading to either a general election or the start of a new Parliamentary session. Under the new plan, Parliament will be dissolved no earlier than September 9 and no later than September 12, until the Queen's Speech on October 14.
Q. So why has the move sparked such anger?
A. There have been fears for a number of months that, should the Government not be able to strike an exit deal with the EU, the PM could look to prorogue Parliament to prevent MPs from attempting to stop the UK leaving without a deal. Critics believe this is what he is doing now. Senior Opposition figures and Tory opponents of a no-deal met on Tuesday to draw up plans to stop the UK crashing out without an agreement. A day later the PM effectively moved to curtail their time to draw up legislation that would prevent exiting without a withdrawal agreement signed-off.
Q. So could a snap general election still be on the cards?
A. Commentators saw the surprise announcement that Chancellor Sajid Javid will set out Whitehall spending budgets next week as a sign that the new administration was ramping up plans for an early election. But inviting the monarch to Parliament for the pomp and ceremony of the Queen's Speech on October 14 would be an odd thing to do if the PM is actually planning a snap election.
If Opposition and rebel Tory MPs unite behind a no-confidence motion against the Government in retaliation against the plans to prorogue, that could force Parliament into a stalemate where a general election is the only resolution.