Not only is this widely known, it is the main method by which multicolor RGB lights can exist, because they are actually a package with red, green, and blue LED

Not only is this widely known, it is the main method by which multicolor RGB lights can exist, because they are actually a package with red, green, and blue LEDs in them, where each color channel is individually “dimmed” using this technique (called pulse width modulation, or PWM) to be able to produce many more colors (much like a TV or LCD/OLED display). The white color produced by full-on of R, G, and B is quite ghastly, so modern ones come with an individual white LED (and frequently a second warm white LED) in the package for a total of four or five individual color LEDs in the single light (RGBW or RGBWW).