Ключевые слова: 6 sigma, abstract, alphabet, ancient, art, branding, business, button, character, clip, concept, design, diameter, education, element, font, formula, graphic, greece, greek, historical, icon, icons, idea, illustration, isolated, knowledge, label, language, letter, material design, math, mathematical, mathematics, measure, modern, radius, scientific, shape, sigma symbol, sign, six sigma, study, symbol, typography, value, word,