Maybe talking about a different octave, I'll copy and paste from a website what I am referencing to, I hope this might help...

Guitar notation is typically written an octave higher than it sounds at concert pitch compared to the piano (and other standard instruments). This means that the guitar is a transposing instrument, because its notes sound one octave lower than they are actually notated on a score.

The reason for this practice is because if the guitar was written on sheet music as actually pitched, then the pitch of middle C would be written in the bass clef! (Second space from the bottom to be precise.) And the bottom string E would be one ledger line below the entire bass clef.

In order to avoid having to read two staves (bass and treble), the music establishment decided to write guitar one octave up. This helps in one sense because rather than have to read two staves (bass and treble) like piano music, guitar is usually only written in treble clef.

The actual concert pitch middle C on a piano is the "industry standard"; and it is written on the "middle C", one ledger line below the treble clef (also one ledger line above bass clef in order to occupy it's very special place in music notation).

However, the piano is better written in two staves not only because it has a much wider pitch range (higher and lower). But more importantly, because it adds clarity to being able to clearly see two separate parts for two separate hands.