The tesla is a unit of measurement used to quantify the strength of a magnetic field. It is part of the International System of Units (SI) and is defined as one weber per square meter. The unit is named after the inventor and electrical engineer Nikola Tesla, who made significant contributions to the development of alternating current (AC) electrical systems. One tesla is a strong magnetic field, equivalent to the magnetic field produced by a large electromagnet. For context, the Earth's magnetic field is about 25 to 65 microteslas, which means it is much weaker than one tesla. This unit is commonly used in physics and engineering, particularly in fields like magnetism and electromagnetism.