A keyboard is basically a grid of switches. The switch is what decides (1) when a keypress is registered, (2) how it feels on the way down and up, and (3) how it sounds. If you understand how a switch works internally, you can make smarter choices than “I heard these are good”—you can predict how a switch will behave in your board, with your typing style, and even how to tune it.
Most MX-style mechanical switches share the same core pieces:
The feel you notice is mostly geometry + spring; the “keypress counts” moment is mostly the sensing method.
These families describe force feel, not necessarily the electrical method. A switch can be tactile and still use different sensing technologies (though MX-style contact switches are most common).
If two switches use the same spring but feel very different (one feels smooth, one feels scratchy and wobbly), which explanation best fits what’s happening inside?
It’s common to assume the spring “is the switch,” but the spring mostly sets return force and overall weight. Scratchiness and wobble are usually about how the stem slides in the housing—rail design, tolerances, and plastics. Keycaps can change leverage and sound, but they don’t change the switch’s electrical actuation point. Firmware and PCB matrix layout don’t alter the mechanical friction you’re feeling.