No other design domain changes as fast as web design.
Due to the rapid changes in technology, designers have to continually meet new and challenging requirements. Touch-based tablets and mobile devices on the one hand, but also new possibilities due to exciting JavaScript based widgets and more stable browser support of cascading style sheets.
But in the end, it is all about the user. Interface design must support the user's experience: Clearly structured information, smooth navigation and tools that can be used by any user, no matter if they use an old-fashioned mouse or their fingertips.