Kinsey suggested that some individuals might be “exclusively heterosexual” (or a zero on the scale), and others might be “exclusively homosexual” (a six on the scale), but many people fit somewhere between the two numbers. The scale was created by biologist Alfred Kinsey in 1948.

Chances are, it’s the one you’re most familiar with, too. There are tons of ways to discover and explore the many hues (so to speak) that exist under the LGBTQ+ umbrella, but one of the earliest metrics popularized was the Kinsey Scale. Thanks to decades of activism, research, and LGBTQ+ individuals sharing their own lived experiences, it’s become common knowledge that sexuality is a spectrum-or, in other words, less black or white and a little more like a rainbow with infinite shades.