The tesla (symbol T) is the SI derived unit of magnetic fieldB (which is also known as "magnetic flux density" and "magnetic induction"). The tesla is equal to one weber per square meter and was defined in 19601 in honor of inventor, scientist and electrical engineerNikola Tesla. One billionth of a tesla is a nanotesla, equivalent to .01 mG or 0.01 milligauss, and it is in nanoteslas that common metric home measurements are made to determine local magnetic field exposure.
This SI unit is named after Nikola Tesla. As with every SI unit whose name is derived from the proper name of a person, the first letter of its symbol is uppercase (T). When an SI unit is spelled out in English, it should always begin with a lowercase letter (tesla), except where any word would be capitalized, such as at the beginning of a sentence or in capitalized material such as a title. Note that "degree Celsius" conforms to this rule because the "d" is lowercase.