André-Marie Ampère was a French physicist and mathematician born on January 20, 1775. He is best known for his foundational work in the field of electromagnetism, which studies the relationship between electricity and magnetism. The unit of electric current, the ampere, is named in his honor, recognizing his significant contributions to science. Ampère's most notable achievement is Ampère's Law, which describes how electric currents create magnetic fields. His research laid the groundwork for many modern technologies, including electric motors and generators. Ampère's work has had a lasting impact on both physics and engineering, influencing countless advancements in these fields.