As a general rule, most Web developers, especially usability enthusiasts, say it is bad practice to use drop-down menus because they are confusing, annoying and oftentimes dysfunctional. From a design standpoint, however, drop-down menus are an excellent feature because they help clean up a busy layout. If structured correctly, drop-down menus can be a great navigation tool, while still being a usable and attractive design feature.

Yes, that’s right: drop-down navigation menus can be user-friendly. Just yesterday Jacob Nielsen the results of his recent drop-down menus study, in which he found out that big, two-dimensional drop-down panels that group navigation options help users to avoid scrolling and can precisely explain the user’s choices with effective use of typography, icons, and tooltips.

These panels appear temporarily and disappear on their own when users move the pointer to another top-level option or to a “regular” part of the screen. You can find more information about Ni