Guidonian hand
In Medieval music, the Guidonian hand was a mnemonic device used to assist singers in learning to sight-sing. Some form of the device may have been used by Guido of Arezzo, a medieval music theorist who wrote a number of treatises, including one instructing singers in sightreading. The hand occurs in some manuscripts before Guido's time as a tool to find the semitone; it does not have the depicted form until the 12th century. Sigebertus Gemblacensis in 1105–10 did describe Guido using the joints of the hand to aid in teaching his hexachord. The Guidonian hand is closely linked with Guido's new ideas about how to learn music, including the use of hexachords, and the first known Western use of solfege.
Shorthand
In Ancient Rome, Marcus Tullius Tiro (103–4 BC), a slave and later a freedman of Cicero, developed the Tironian notes so that he could write down Cicero's speeches. Plutarch (c46-c120 AD) in his "Life of Cato the Younger" (95-46 BC) records that Cicero, during a trial of some insurrectionists in the senate, employed several expert rapid writers, whom he had taught to make figures comprising numerous words in a few short strokes, to preserve Cato's speech on this occasion. The Tironian notes consisted of Latin word stem abbreviations ("notae") and of word ending abbreviations ("titulae"). The original Tironian notes consisted of about 4000 signs, but new signs were introduced, so that their number might increase to as many as 13,000. In order to have a less complex writing system, a syllabic shorthand script was sometimes used. After the decline of the Roman Empire, the Tironian notes were no longer used to transcribe speeches, though they were still known and taught, particularly during the Carolingian Renaissance. After the 11th century, however, they were mostly forgotten.