Complex sentence: It is used in situations where you have several PCs, with a monitor connected to each, but only want to have one keyboard and mouse on the desk--similar to a KVM switch without the Video.
Split into simpler sentences: It is used in situations where several PCs are used together, with a monitor connected to each, but are to be controlled by one user. The user needs only one keyboard and mouse on the desk--similar to a KVM switch without the Video.