section_path: Lexicographic conventions/Unit symbols and the values of quantities
section_name: Unit symbols and the values of quantities
paragraph_text: Unit symbols and the values of quantities
  
  Symbols of SI units are intended to be unique and universal, independent of the context language. The SI Brochure has specific rules for writing them.
  
  In addition, the SI Brochure provides style conventions for among other aspects of displaying quantities units: the quantity symbols, formatting of numbers and the decimal marker, expressing measurement uncertainty, multiplication and division of quantity symbols, and the use of pure numbers and various angles.
  
  In the United States, the guideline produced by the National Institute of Standards and Technology (NIST) clarifies language-specific details for American English that were left unclear by the SI Brochure, but is otherwise identical to the SI Brochure. For example, since 1979, the litre may exceptionally be written using either an uppercase "L" or a lowercase "l", a decision prompted by the similarity of the lowercase letter "l" to the numeral "1", especially with certain typefaces or English-style handwriting. The American NIST recommends that within the United States "L" be used rather than "l".