Lesson 4

1. Lesson 4
WEB SERVER

2. WEB SERVER
A web server is a computer that runs
websites. It's a computer program that
distributes web pages as they are
requisitioned. The basic objective of
the web server is to store, process and
deliver web pages to the users. This
intercommunication is done using
Hypertext Transfer Protocol (HTTP).
These web pages are mostly static
content that includes HTML
documents, images, style sheets, test
etc. Apart from HTTP, a web server also
supports SMTP (Simple Mail transfer
Protocol) and FTP (File Transfer
Protocol) protocol for emailing and for
file transfer and storage.

3. The main job of a web server is to
display the website content. If a web
server is not exposed to the public and
is used internally, then it is called
Intranet Server. When anyone requests
for a website by adding the URL or web
address on a web browsers (like
Chrome or Firefox) address bar (like
www.economictimes.com), the
browser sends a request to the Internet
for viewing the corresponding web
page for that address. A Domain
Name Server (DNS) converts this URL to
an IP Address (For example
192.168.216.345), which in turn points to
a Web Server.

4. The Web Server is requested to present the
content website to the user’s browser. All
websites on the Internet have a unique
identifier in terms of an IP address. This
Internet Protocol address is used to
communicate between different servers
across the Internet. These days, Apache
server is the most common web server
available in the market. Apache is an open
source software that handles almost 70
percent of all websites available today.
Most of the web-based applications use
Apache as their default Web Server
environment. Another web server that is
generally available is Internet Information
Service (IIS). IIS is owned by Microsoft.

5. EXAMPLE OF WEB BROWSER
 Apache Web Server
Apache is currently the most
used web server in the world.
Founded in 1996, it’s now
maintained by the Apache
Foundation. Its freeware, and
compatible with Linux, Windows,
FreeBSD, Mac and several other
platforms.

6.  IIS
Also one of the most popular web
server examples. IIS belongs to
Microsoft. IIS stands for Microsoft
Internet Information Services. It
comes with the Windows Server
operating system. It’s configurable
through a graphical interface.

7.  NGINX
It’s one of the most popular web
server software. NGINX was
developed by Igor Sysoev in 2002.
Also, it is not a standalone web
server example. NGINX is a different
example because it works as a proxy
server, together with another web
server application like Apache.

8.  APACHE TOMCAT
Tomcat is a free web server,
specialized in Java Servlets. In other
words, it’s a Java container. Apache
Tomcat was initially developed by
Sun Microsystems, and then it was
transferred to the Apache Software
Foundation in 1999. By the way,
Tomcat usually works under port 8080
and supports PHP, ASP.net, Perl,
Python, etc.

9.  LIGHTHTTPD
Lighthttpd was initially developed in
2003. Basically, it’s not a very
common web server software
example for public web sites on the
internet. It has a big advantage: as
the name says, it’s the lighter HTTP
server available. It uses a very low
memory, CPU and disk space.