Usually it takes a person with quite a bit of experience to be able to Successfully setup, maintain, and configure a web server. The problem with this is that there are not enough of these experienced people to prepare a web server for all of the individual web sites on the internet today.
One way to help fix this problem is to use virtual web servers. A virtual web server allows one very experienced person to setup a single server that will be able to host many different web sites across many domains. This also allows different web sites to be configured individually and be able to use more resources than they would be able to use if they were not hosted on a virtual web server.
A virtual web server allows each web site to have its email, FTP access, and many other configuration files to be configured exactly the way you want them to be. Also a virtual web server allows access to different types of databases which can make your web site more dynamic.
Many virtual web server plans allow unlimited email addresses and built-in spam filters and virus protection. They also allow unlimited anonymous and non-anonymous FTP sites, so that you can offer file upload and downloads to your clients.
However the best feature of a virtual web server is that you have complete control over how your web site is configured to run, so you can do almost anything that you want to do. You do not have to be an expert, because many of these services offer a management tool, so that you can do all of the configurations without knowing exactly how to do it by hand.