The Lines from bottom to top: G B D F A and the Spaces (bottom to top): A C E G In the Grand Staff there are three more names. They are called “Ledger Lines/Spaces: the space above top line (A) is B, then line C and space D
The Treble Clef Sign is also called the “G-Clef Sign” since it circles the G-line. The Bass Clef Sign is also called the “F-Clef Sign” since it has dots above and below the next-to-top (F) line.
Below: Both Treble and Bass Key Signatures for all 15 Major Keys and 15 minor keys. Remeber: The relative minor of each Major is the name of the 6th degree. (C-Major has the same key signature as a-minor, etc)
The creation of ‘keys’ made it possible to change the range (high/low) for various voices and Instruments. The human voice has a limited range. For example, the regular ‘female voice’ “sounds” ONE FULL OCTAVE (8 tones) above the ‘male voice’. All instruments are not ‘tuned’ to the Key of C. The Trumpet, for example, is mostly tuned to B-flat. In an orchestra, only the piano and stringed instruments are ‘tuned’ to the Key of C. Looking at an Orchestral Score, you will find different key signatures throughout. To do otherwise, you would for certain have chaos and horrible sounds.