I have a centos 5.5 64 bit xen vps. I have a php script that automatically sends confirmation emails for people who sign up, it's not sending it right now and i believe it's because i don't have a webmail installed, right? if so then I have to install a webmail, I don't have any hosting panel.
I googled, but there's so much that I do not understand, I would like to ask about it before i install anythihg:
1- What software do you have to install in order to have a webmail?
2- Is roundcube and similar software just an interface or do they install a webmail too?
3- zimbra, postfix...what are they? are they email servers and then i have to install rouncube as an interface for them, or are they just like roundcube?
4-what is the difference between pop3 and other types of email and is pop3 the best one to use?
5- Do webmails block spams or do i have to install another software for spammers and hackers...
6- would i have to manually configure the webmail in order for it to work with my script, or not?
Note
if you answered every question I'll be so thankful, but i think it's too long, so if you don't have time to answer everything, please just answer the first question, and I'll google to get answers about the rest, or I'll ask them on other forums.