In the UK Parliament the importance of a vote is indicated by underlining of items on the "whip", which is the name of the letter the Chief Whip sends to all the MPs in their party at the start of the week. This letter informs them of the schedule for the days ahead, and includes the sentence, "Your attendance is absolutely essential" next to each debate in which there will be a vote. This sentence is underlined once, twice or three times depending on the consequences that will be suffered if they do not turn up, hence the origin of the terms "one-line whip", "two-line whip" and "three-line whip". The actual vote they are to make is communicated to them in the chamber by hand signals during the division when the time comes (usually after the division bell has been rung). Even though it is more important to the result of any division than the debate, neither these instructions, which are visible to everyone in the chamber, nor the "whip" letter at the start of the week, are recorded in "Hansard", as they are considered a matter internal to the political party; indeed, the system exists because any explicit direction to an MP as to how they should vote would be a breach of parliamentary privilege.