This document provides a summary of key musical concepts related to pitch, including:
1) Pitch refers to how high or low a musical note is. It is measured by its frequency in units called Hertz.
2) The standard tuning note is A above middle C, which vibrates at 440 Hz.
3) There are 7 letters (A-G) used to name notes in the Western musical alphabet, which repeats in octaves up and down the range of instruments.
4) Clefs like treble and bass clef assign letter names to lines and spaces on the musical staff and allow notes to be visually represented.