There are many situations where a user needs to use a single keyboard & mouse with 2 or 3 computers or CPUs (with either one monitor or more than one monitor). Is this kind of setup possible? Yes. It is possible with either using a software or hardware. Both the approaches have its own pros and cons.
There are many free and licensed software available to download to make use of single keyboard & mouse with 2 or more computers.
There is a special hardware called KVM Switch which can be used to share single keyboard, single mouse and single monitor with multiple CPUs. The number of CPUs that can share the same keyboard, mouse and monitor depends on the cost and specificaiton of KVM switch.
A KVM switch costs around Rs 2500 in India which can share same keyboard, mouse and a monitor with 4 CPUs.
Share Keyboard & Mouse
|Cannot share Monitor|
|KVM Switch||Share Keyboard, Mouse & Monitor||Not Free|