Operatic solos, also known as ARIAS, are pieces of music sung by a single voice with orchestral accompaniment. They are typically found in operas, oratorios, and cantatas, and often feature complex vocal techniques such as runs, trills, and ornamentation. ARIAS are usually composed in a specific musical form, such as a da capo aria or a rondo. They are often used to express the emotions of the characters in the opera, and can be some of the most memorable and beautiful pieces of music in the genre.