Servers are generally computers that provide resources to multiple people, and often have no person "sitting at the keyboard." Server hardware is more robust, with storage redundancy to reduce downtime due to failures and higher speed/capacity components more closely selected for the duties they perform.

Servers can serve all kinds of things, such as files, web pages, print jobs, email, etc. Depending on what resources you need and how heavy they are, you may need several computers configured as servers, or only one. They might be located in your office, or in an enterprise-class datacenter. If you have any at all, they will benefit from proactive administration and maintenance. A server administrator is like having somebody "at the keyboard" who monitors the processes, checks logs, watches for security breaches, applies software updates, handles system alerts, and generally makes sure things continue to run smoothly by fixing small issues before they become big problems. I use remote administration tools and can manage your servers as part of my daily routine without travel time or disrupting your business.