A common myth in singing is that only women possess a falsetto voice, or that men should avoid it to maintain "masculine" vocal qualities. In truth, the falsetto is "half the voice" for every human being. Regardless of gender, neglecting this register means neglecting the very mechanism that allows you to sing on pitch.
Often referred to as the "head voice" or the "light" voice, falsetto is a texture of sound created when the stretching muscles—the crico-thyroid (CT) muscles—are active. These muscles work either in isolation or in a dominant coordination with the closer muscles (the arytenoids).
You can easily find this register by starting in your "regular" chest voice at the bottom of your range and sliding upward until your voice "breaks" or "yodels" into a lighter, thinner sound. That flip is your crico-thyroid system taking the lead.
The falsetto register is responsible for allowing us to sing both higher and lower because it is the primary regulator of pitch. Without a functioning falsetto/CT system:
The goal of vocal training isn't just to sing in one register or the other. When we develop the falsetto and coordinate it with the chest voice, we achieve a dynamic balance. This "full voice" occurs when both the stretchers and the closers are strengthened and working together in harmony.
While men use falsetto as an obvious stylistic color in many popular music genres, its internal health is vital even if you never intend to sing with a "breathy" or "light" sound. It provides the flexibility and range necessary for the entire voice to emerge.
Falsetto is for everyone. It is the stretching mechanism that gives your voice its height and its health. By embracing the "light" side of your registration, you secure the coordination needed to sing freely, accurately, and fully across your entire range.