LINUX,APACHE,PHP & MYSQL

For intsallation
#yum install apache
#yum install php
#yum install mysql-server mysql

Open configuration file of apache server.
#vi /etc/httpd/conf/httpd.conf
a)search Load module
LoadModule php4_module modules/libphp4.so
b)Search directoryIndex
DirectoryIndex index.html index.html.var index.php
c) search AddType
AddType application/x-httpd-php.php
save the file
and restart apche service.
Open config file of PHP
#vi /etc/php.ini
a) search doc_root
doc_root="/var/www/html"
b) search file_uploads
file_uploads=off
Open config file of mysql
#vi /etc/my.cnf
service restart.
you can point your browser to http://localhost and you should see a welcome page

To test if php is running, go to /var/www/html and create an index.php file with the content belowand refresh your browser again