Design, navigation and usability

Good design along with content and handy navigation is one of the main criterias of site's success. There are several basic web-design clasifications:

• by used technologies (HTML, DHTML+CSS, JS, Flash, Ajax etc.)
• by assumed client and it's screen size (common, "rubber", for mobile devices, for non-visual clients)
• by markup method (table-based, div-based or mixed)
• by cross-browser compatibility
  

What are criteria of good design? First o all , it has to to meet next requirements:

• Compatibility with the most populat browsers (at least IE 5-7, Mozilla, Firefox 1.5-2.0, Opera 7-9)
• Readability (text color should be contrast to background and fonts - large enough)
• Quick loading. For sure, loading time varies for different providers and some other conditions, but you have to remember, user won't wait too long - he'll just pass to another site.
• Ability to keep proper view with turned off images and on displays of mobile devices
• Corporative colors and style utilization, if there are any
• And it have to be attractive for you, of course.
  

Depending on site purposes and used technologies, page should weight no more than 100KB-1MB, although there are exceptions. As to readability, best are dark fonts on birght background. Column width should be no more than 80-100 symbols and total page height - no more than 2-3 screens.

Navigation should be logical and clear, because if user won't find what he need in 3-4 clicks, he probably will search on other site. Menu number and structure, necessity of additional navigational elements (eg. «bread crumbs», sitemap etc.) are determined due to site structre and pages quantity.