<P> The standard form of rap notation is the "flow diagram", where rappers line up their lyrics underneath "beat numbers". Hip - hop scholars also make use of the same flow diagrams that rappers use: the books How to Rap and How to Rap 2 extensively use the diagrams to explain rap's triplets, flams, rests, rhyme schemes, runs of rhyme, and breaking rhyme patterns, among other techniques . Similar systems are used by musicologists Adam Krims in his book Rap Music and the Poetics of Identity and Kyle Adams in his work on rap's flow . As rap revolves around a strong 4 / 4 beat, with certain syllables aligned to the beat, all the notational systems have a similar structure: they all have four beat numbers at the top of the diagram, so that syllables can be written in - line with the beat . </P> <P> Many computer programs have been developed for creating music notation (called scorewriters or music notation software). Music may also be stored in various digital file formats for purposes other than graphic notation output . </P> <P> According to Philip Tagg and Richard Middleton, musicology and to a degree European - influenced musical practice suffer from a' notational centricity', a methodology slanted by the characteristics of notation . </P> <P> In some countries, new musical notations can be patented . In the United States, for example, about 90 patents have been issued for new notation systems . The earliest patent, U.S. Patent 1,383 was published in 1839 . </P>

When did the development of standard notation occur