 At the center of the surprisingly vast world of mechanical keyboards is the keyswitch. And its most basic type is the linear keyswitch, often denoted by a red or black colored stem. The linear switch is smooth, relatively quiet, and often preferred for applications where speed is important, such as gaming. Its design provides no tactile feedback to the user before actuating and registering a keystroke. Exhibiting a linear relationship between force and travel distance. Differences in stem design and lubrication can make one linear feel smoother than another, but most variations are due simply to the type of spring used inside. Commonly, red switches require relatively low compression force, and black require more force to actuate.