What does the phrase 'first past the post' mean?

• In each constituency, the candidate who gets the most votes is elected
  Explanation:

  "First past the post : A system of election in which the candidate with the largest number of votes in a particular constituency wins a seat in Parliament."
• If no political party wins a majority, two parties may join and govern together
• If an MP dies or resigns, there will be a fresh election
• The Speaker will be chosen by other MPs in a secret ballot