As a web designer, I can hardly find enough time nor space to put nicely designed drop-down menus. Part of the reason why even this site lacks drop down menus is the fact that it would slow the site down greatly, as it’s slowing down too much due to too much information.
On the bright side, drop-down menus can come in handy for users to navigate your site. There’s a lot of old javascript ones and the new CSS & AJAX ones that I like.
Smashing Magazine doesn’t get into the nitty gritty javascript and CSS but they do go over many of the physical aspects behind how to design a drop-down menu, you can check it out here.

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