Content must be relevant to the product or service you are offering over the web. If you sell art, you need to have a gallery of your work so people may determine if your art is in line with what they want. Testimonials help as well. The most important rule in developing content for your site is to Think like the visitor who is coming to your site is thinking . If you get the content right, you'll have great success from your site.
Many sites offer a very wide variety of information mixes.
Not all of this information is relevant or even of interest to every visitor to the site. Many sports sites, for instance, allow you to personalize, or customize the site, by asking you to register your preferences. If you don't register, when you come to the site, you get a mix of football, figure skating, golf, horse racing, basketball and hockey news and scores. But if you register your preferences, and let that site know your only interests are golf and football, then every subsequent time you visit that site, the only information displayed on the very first page you come to will be golf and football news and scores, saving you the need to dig through often complex menu- driven navigation systems. This also works on business sites to allow certain clients to be automatically identified as, say, buyers of a particular product in your line, and their page gives them immediate access to their order history, account status, and other pertinent data, without having to log in and click through menus every time.