/sbin/service httpd status
remember that your /sbin directory is not in the default user profile PATH variable.
if apache is not instlalled type
#yum -y install httpd
chkconfig httpd on
service httpd start (if this doesnt work remember the /sbin)
STEP 4 go to your browser and type http:/<yourcompuernamehere> or that http://localhost/index.html
that should work.