Adjacent colors 90 and 60 degrees

Quick answer：

Adjacent colors refer to hues that are next to each other on the color wheel. A 90-degree color scheme is known as complementary colors, where the hues are directly opposite each other. A 60-degree scheme is considered analogous colors, which are next to each other but not directly opposite. These color schemes are commonly used in design and art to create harmonious and cohesive color palettes.