1. Machine: A hardware device is called as Machine.
2. Host: If we assign any address to a machine to identify it, is called Host.
3. Client: A Host PC which is not able to do the job and sending the request to some other PC in network to process the job.
4. Server: A PC which is processing the client's request is called "server".
5. Work Station: A Host PC which is able to perform every job by itself.
6. Process: A foreground process which is running on the system is called process.
7. Daemon: It is a background process.
8. Multitasking: Which allow you to perform a multiple task in a single system.
9. Multi User: Multiple users should be able to login to a single system.
10. Distributed system: A group of systems integrated (or interconnected) to perform a job.
11. False Tolerance: A distributed system which, if any one the system is crashed then also if your able to perform the job successfully is called "False Tolerance".
12. Spanning: If your able to write the data in the multiple disk alternately, simultaneously or sequentially is called Spanning.
13. Kernel: Communication between Hardware device & user. Kernel nothing but a basic device driver.
14. Shell: It acts as a interface between the kernel & user.
