When most people say server what they really mean is web server. The basic function
of a web server to is provide web pages to a web browser. This can be a relatively
simple process involving a web server program such as Apache or IIS on a single
physical server or it can be part of a complex cluster of multiple database, application
and web servers on separate physical servers configured to act as a single unit.
Web Server Fundamentals
Although there are many means to implement a web server the fundamental way a web
server provides web pages is by storing the content of the web page in files on
a hard drive. It provides these files using Hypertext Transfer Protocol (HTTP) to
a user that requests it through his web browser as a web page.
Many web servers include other functions such as email, File Transfer Protocol (FTP),
and programs to create web pages. A web server also acts as the front-end for application
servers and provides access to application programs. The web server is an integral
part of making applications available via the web.
When numerous companies have their web sites on a single web server it is called
a virtual web server or virtual hosting. When the web server has a single company's
web site it is called a dedicated web server or dedicated hosting. A dedicated web
server also can be part of a cluster to improve throughput and reliability.
Web Server Hosting
A web server can be hosted in corporate data centers, but the trend is to outsource
them to hosting companies for increased reliability, security, 24/7 monitoring,
and lower costs. If possible, find a hosting company that has a tier 1 data center
for increased levels of redundancy and improved system uptime.