startup items...

Hi - I have the following items in the startup on my macbook air. What do these do and which of them are unnecessary?
DevDetectListener
iTunesHelper
System Events
Microsoft AU Daemon
HP Product Research (All Users)
HPEventHandler (All Users)
HP Scheduler (All Users)

Thanks!

All of them, except iTunesHelper have been created by application that you have installed.

I think DevDetectListener might be related to camera software
Microsoft AU daemon looks like an AutoUpdate feature for Microsoft Office
HPxxxxx can be related to some sort of HP software.

What version of OSX are you running ?

Cheers ... McBie