What does Macbeth consider doing after hearing he will be King one day?
(ACT 1, Scene 3) *

Banquo laughs at the prophecies but Macbeth is excited, especially as soon after their meeting with the witches Macbeth is made Thane of Cawdor by King Duncan, in return for his bravery in the battle. ... No one is quite sure who committed this murder, and no one feels safe, but Macbeth is crowned king.

  this riddles' answer is library.

  the "leaves" are a reference to the books' pages that the library contains; the branches are a network of libraries that connect multiple libraries' collections, resources, and items in a system of a common database, integrating them; the branches' organization are a useful management tool for coordinating the multiple collections many libraries have.