Cotton is the basic textile raw material processed worldwide in spite of strong competition from intensively developing other natural fibers and man-made fibers. For years the quality of cotton has been assessed in an organoleptic way by cotton classers. Today there are plans to replace subjective visual grading by objective instrumental measurement. The color grade of cotton is determined by the traditional cotton color attributes degree of reflectance (Rd) and the yellowness (+b), which are measured instrumentally. The aim of this work was to clarify meaning of the traditional cotton color attributes and how it measured. In addition to, demonstration for the classer and instrumental color grading, as well as, benefit from some previous articles in utilizing different aspects of cotton color attributes. This work provides basics and necessary information's for those interested and working in field of the cotton classification.