In an effort to bring cost down, many keyboards are now manufactured with membrane switches rather than mechanical switches. Membrane switches are cheap to manufacture, but they lack the personality of traditional, mechanical key switches. For those who want to have an enjoyable experience while typing, rather than just a tolerable one, mechancial keyswitches are still the way to go. There are hundreds of options to choose from when picking keyswitches, but all keyswitches can be broken down into 3 categories: Linear, Tactile, and Clicky.
Linear switches are going to be the most familiar to those who have used mechanical keyboards in the past. These switches are buttery smooth from the moment you start pressing the key, until it "bottoms out". Most linear switches will gradually increase in the amount of pressure required to press the key as it is pressed further and further down. This means that it is very easy to press the key at first, but it will resist your finger a tiny bit more if you try to press it all the way down to the bottom. This provides an almost "springy" sensation as you type.
Tactile switches provide a unique and satisfying typing experience. Like Linear switches, most of these switches actuate somewhere in the middle of being pressed, before the switch "bottoms out". Tactile switches are designed with a slight bump, right around this point of actuation, so there is physical, tactile feedback when your key press gets registered. This can be helpful to those wanting to type without bottoming out, and it's a preferred tactile experience for many typists over that of the buttery smooth feel of a Linear switch.
Depending on who you are, Clicky switches might be the most fun switches in existence, or the most annoying. Clicky switches offer the same tactile bump that Tactile switches do, but are designed to also make a *click* noise right when your key actuates. This audible, tactile typing experience can be immensly enjoyable to the typist, but is often a source of great annoyance to others. These keyboards can be quite loud! Clicky switches are a great choice for those with home offices who want an immersive typing experience, with both audible and tactile feedback to their key presses. This key switch is also great for anyone seeking to annoy fellow co-workers or loved ones who must endure all the clicking and clacking of a keyboard they wish they had.