What is Early notation suggested melodic contours using small ascending and descending signs called?

Early notation that suggested melodic contours using small ascending and descending signs is known as neume notation. This system was used in Gregorian chant and other early forms of music to indicate pitch and melodic movement without specifying exact notes. Neumes represented patterns of sound and helped singers remember the melodies. The notation evolved over time, leading to the development of modern musical notation.