Experts offer widely different opinions as to which platform works best for web sites. In the end, the choice depends largely on what you want to do with your site. For example, if you'll be using Microsoft applications such as MS SQL (a database program) or Microsoft FrontPage (a web authoring tool), you might be more comfortable operating your site on a Windows NT platform. Since NT, MS SQL and FrontPage are all Microsoft products, they are more compatible with one another. On the other hand, many engineers prefer the flexibility, security, and control of Unix servers. Unix also allows for more web sites per server, lowering the cost of hosting per account.

As your site grows in size and complexity, in all likelihood you'll decide that a particular platform is desirable. It's best to anticipate this contingency and choose a web host that offers multiple platforms and backs them up with technical expertise.

Redundancy
No matter how excellent the equipment, no matter how expert the engineers, technology fails occasionally. A web host with multiple routers and switches, secondary servers, and UPS systems with backup generators can provide consistent, high-speed access and guarantee at least 99% uptime. Web hosting companies, unlike Internet Service Providers (ISPs), have high-speed lines connected to more than one Internet "backbone" provider. This is crucial to reliable web site performance, since network service can be compromised by technical glitches and unexpected surges in traffic. A redundant network design allows a web host to direct traffic away from Internet "hotspots" and along the fastest routes - and your site remains available even if one network's service is interrupted. The best hosting providers will have diesel generators that can operate the servers for up to 7 days independently; off-site tape storage; redundant servers; and links to different network providers - all to make sure that your site will remain available through every crisis.

Reliability
Excellent web hosting providers can offer this guarantee because they've invested in the best automatic monitoring equipment; hired experienced engineers who can anticipate problems and emergencies; and installed redundant backup systems to take over the moment anything goes wrong. If a web host guarantees only 95% uptime, keep in mind that this translates into 8.4 hours of down time per week: the equivalent of a "closed" sign on the door of your 24-hour business.

Security
It takes many layers of Internet security, from password protection to firewall barriers, to prevent determined hackers from wreaking havoc with your Web data. Most hosting companies offer some assurance that their network and software are protected from unwanted intrusions such as spamming and hijacking. Make sure the hosting company you choose has enough security measures in place to ensure that your data is completely protected.

Servers
Although it's possible to host a web site on the CPU of an average personal computer, responsive web sites require high-speed SCSI disk drives, error-correcting RAM, and the most powerful microprocessors available. Reliable providers host their sites on equipment built to withstand the constant bombardment of web traffic.

Speed
Web hosting companies typically connect to the Internet through T (Transmission), OC (Optical Carrier), and DS (Digital Signal) lines. Many smaller web hosting providers still use T1's to connect your site to the world at a rate of 1.544 megabits per second. You should look for a hosting provider that uses redundant multiple transmission line and offers customers the bandwidth they need for multiple user sessions on their site at any given time. The best hosting companies use redundant lines to ensure that customers' sites remain responsive even if their primary Internet connections are temporarily unavailable. It's a good idea to determine which providers offer backup connections fast enough to maintain your site's performance in the event of a primary line failure. In addition to offering the fastest network connections, a host should provision its lines and circuits to use less than 50% of available bandwidth. Overburdened network connections will inevitably result in poor site performance - in fact, a lightly used T1 line will transfer data faster than an overused T3 connection. Be sure to ask hosting companies about network capacity and utilization to make sure that your site will benefit from the fast network connections they've advertised.