This hue is inspired by the fluorescent yellow of the classic highlighter, engineered for maximum visibility on the page. Its brightness comes from dyes that absorb ultraviolet light and re-emit it as visible yellow-green, making text look almost unreal under natural or artificial light. First developed in 1963 by Dr. Francis Honn at Carter’s Ink and popularized in 1971 by Stabilo’s Boss marker, the shade became the standard. Today, yellow accounts for about 85% of highlighter sales because it emphasizes without obscuring the words beneath. As a bonus, the fluorescence tends to drop out in photocopies, so marked passages don’t muddy duplicates.