Maria Callas was a renowned Greek-American opera singer who achieved international fame during the 1950s and 1960s. She was known for her powerful voice, dramatic interpretations, and passionate performances. Her repertoire included works by composers such as Verdi, Puccini, and Bellini. She was also known for her collaborations with other singers, conductors, and directors. Callas was one of the most influential singers of the 20th century and is still remembered today for her remarkable talent.