please can someone tell me other types of application programs which php can be used to develop other than database driven applications. if possible some suggested reading stuffs on their howtos. any help is enormously appreciated.

You can search 'php report', there are many results.Some programs are free like 'php reports generator'
,,You can have a try.

thank you mushget. however i mean apart from using php to develop database driven applications , what are other types of applications that php can be used to develop. for instance can php be used to develop real time applications.

Anything you want basically. BUT if you need to store information for longer than 20 minutes (session timeout) it requires a database of some kind.

If anything is involved then PHP alone can't create desktop like app - you need JS framework/maybe Flash things...etc.
PHP is good for background jobs

what is socket in php? when is it needed? i understand is related to a network but i have been running my sites on the internet which is a network and i have never used any socket functions in my code. please help. thanks in advance.

Basically a "socket" is a communications port for software or hardware to pass messages through