Gregorio Ricci-Curbastro was an Italian mathematician born on February 12, 1850, in the town of Castelnuovo di Garfagnana. He is best known for developing the mathematical framework of tensor calculus, which is essential in various fields, including physics and engineering. His work laid the groundwork for later advancements in the theory of relativity. Ricci-Curbastro collaborated with his student Tullio Levi-Civita to further refine tensor calculus, leading to its widespread adoption in the early 20th century. His contributions significantly impacted the study of differential geometry and general relativity, influencing many scientists and mathematicians in subsequent generations.