E&M

E&M may stand for:

• E and M signaling, a type of supervisory line signaling that uses DC signals on separate leads
• Encrypt-and-MAC (E&M), an approach to authenticated encryption
• Electromagnetism, sometimes also called electricity and magnetism, a branch of physics
• Electromechanics, combines electrical engineering and mechanical engineering
• Evaluation and Management Coding, a medical billing process in the United States
• Exchange and Mart, a defunct long-established British sales publication

• Mechatronics, a portmanteau of electronics and mechanics