There are two main operating systems available for shared or virtual hosting, the UNIX and the WINDOWS platform, both of which have their own particular features.
Developed by Microsoft, the Windows Servers are specifically built for their advanced applications (MS SQL, FrontPage and Access) or compatible ones. It is also designed to link up the database applications to the web through programs like Active Server Pages (ASP), Visual Basic Scripts and Cold Fusion. The upside is that a Windows Server is very accessible, as long as the website owner has a web hosting package to remotely administer it through a GUI-based program or control panel, if they have control of their server.
The plus side is that Windows servers are more manageable and can be multiplexed more easily because of the developments and advances in the .NET technology. That makes it ideal to use if one does not intend to subscribe to a shared server (although the system will work for those as well).
In terms of technical help or after sales support systems, as well as security measures and integration of the products, Microsoft is an industry leader. If the consumer is knowledgeable and comfortable with using Microsoft products, then it certainly makes sense to use this platform. For those just beginning to learn the intricate system and can not put in the man hours required to administer the system, however, it may not be a good option.
The alternative of choice would be the UNIX platform, if the client can not warp their head around the Microsoft programs.
The UNIX platform is not, by any means, and inferior product. As a matter of fact, majority of websites are hosted in the UNIX platform today. The technical requirements for this platform are a lot simpler and very flexible. It also has that desirable "shell environment" even while it offers a very healthy connection for heavy traffic and server loads. The "shell environment" gives the website owner complete access and a lot of flexibility. That means that they can manage their sites and customize it to their specifications anywhere they can access it with their text based systems without any need to purchase expensive and specialized software. The platform also allows for large data transfers for multiple sites.
The greatest feature of the UNIX platform is that really can boast of a 99% uptime, something that Windows servers are rarely able to accomplish. It takes a bit special tweaking for Microsoft systems to achieve this "uptime" and most webmasters opt for the UNIX platform because of this fact.
Website newbies are also advised to use the less complicated and more inexpensive UNIX platform. While a Microsoft server will support the FrontPage server extension, so would the UNIX platform. But unless the software is specifically designed to be compatible with the Microsoft system, that platform will not support the application.