Machinist Mate

The Machinist’s Mate (MM) is a key enlisted rating in the United States Navy, established in 1884 to operate, maintain, and repair shipboard mechanical equipment. Originally, Machinist's Mates were essential for operating steam engines aboard early steel warships, adapting over time as naval propulsion evolved from steam to diesel and nuclear power. During World War II, MMs played a vital role in keeping the Navy’s vast fleet operational across multiple theaters. Today, Machinist’s Mates serve on surface ships, submarines, and at shore facilities, ensuring the functionality of engines, auxiliary systems, and propulsion machinery critical to naval operations.