Server Programs: 

Server programs are dedicated computer programs that run as services and serve the needs or requests of other programs. These services may run on a dedicated hardware or on the same computer as the requesting program. Also, one on more services may run on  the same computer hardware.

Some common examples of different types of server programs are:  

• Web server - for hosting websites.  
• Print server - manage multiple print requests for multiple printers.  
• File server - manages the storage and retrieval of shared computer files.  
• Database server - provide database services to other computer programs.  
• Mail Server - manages and transfers electronic mail messages.