That's called an accidental sign.
In standard musical notation the sharp sign (#) denoted a note raised by a half step. There are also half sharps and 3/4-sharps for raising a note by 1/4 tone or 3/4 tone respectively.
The flat symbol (b)
Call sign or identifier.
Five Man Electrical Band in 1971.
It is the call sign for the station. All radio stations are assigned a call sign by the Federal Communications Commission, or FCC.
tesla
To sign "Are you mad at me?" in American Sign Language, you would sign: "YOU MAD ME?" while raising your eyebrows and looking concerned.
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In standard musical notation the sharp sign (#) denoted a note raised by a half step. There are also half sharps and 3/4-sharps for raising a note by 1/4 tone or 3/4 tone respectively.
Note is a musical term. It is a sign representing the duration and pitch of a musical sound.
coven leader was his call sign.
The flat symbol (b)
In American Sign Language, the sign for "one" is formed by raising your index finger and holding it up. This sign is used when indicating the number one in counting or to emphasize singularity.
Call sign or identifier.
The coda sign in musical notation indicates a specific section of music that should be skipped to a later part of the piece. It helps musicians navigate complex musical structures and ensures that the piece is played correctly from start to finish.
Five Man Electrical Band in 1971.
The sheet music sign in musical notation, also known as the clef, indicates which notes correspond to which lines and spaces on the staff. It helps musicians know the pitch of the notes they are reading and guides them in playing the correct musical tones.