notation

noun3

1. •
   The act, process, method, or an instance of representing by a system or set of marks, signs, figures, or characters.
2. •
   A system of characters, symbols, or abbreviated expressions used in an art or science or in mathematics or logic to express technical facts or quantities.

   • This section lists all algebraic notation used in this book.
   • The notations used in the two books differed.
3. •
   A specific note or piece of information written in such a notation.

   • She made a notation in the margin of the book.