Solfa

Solfa, also known as solfège or solfeggio, is a mnemonic system for teaching music that uses syllables to represent the notes of a scale. ¹

Explanation
Solfa is a way to teach music by assigning syllables to each note of the scale, such as “doh” for the note “C” on a piano. This allows singers to learn music by hearing it and verbally naming the pitches, instead of reading music on a staff. ²
History
The Italian monk Guido D’Arezzo is credited with developing solfa in the 11th century. He used the initial tones of the “Hymn to St. John” to train singers. ³
Benefits
Solfa helps train the musical ear for tasks like playing by ear and improvising. It focuses on pitch relationships and functions within a tonal system. ³If you learn a melody as solfa, then its easy to transpose to any key. For example mi, re, do, re, mi, mi, mi is the start of Mary Had a Little Lamb. In the key of C, do is C, re is D and mi is E. If you make Do to be the note A (as in the key of A), the notes are A, B, C#. ³
Abbreviations
DOH can be abbreviated DO, and SOL as SO.

Citations