Apache Installation And Configuration Under Ubuntu/Debian

Service Used   : httpd (Hyper Text Transfer Protocol Daemon)
Port used                : 80
Document Root : /var/www
Configuration File   : /etc/apache2/apache2.conf

#  /etc/apache2/ports.conf     // conf file of apache ports and ip address
#  apt-get install apache2
#  /etc/init.d/apache2 start

But apache2 has configured the virtualhost by default in ubuntu,you can see in the bottom of the configuration file " Include sites-enabled "

# /etc/apache2/sites-available/default

   Copy the default conf file and paste with your website name

# sudo cp /etc/apache2/sites-available/default /etc/apache2/sites-available/testsite
# vim /etc/apache2/sites-available/testsite  
<virtualhost *:80>
            ServerAdmin webmaster@localhost
            DocumentRoot /var/www/
        </virtualhost>

Enable the website by

# sudo a2ensite testsite