Linear switch feels smooth, no tactile bump, and no audible click as the keypress registers. Each keypress does not generate noticeable sound noise.
Tactile switch gives tactile bump on keypress, but it has no audible click. Each keypress generates noticeable sound noise.
Clicky switch is known as Tactile + Clicky switch, it gives tactile bump and also audible click feedback. Each keypress generates loud sound noise.