Nikon 18-105MM F3.5-5.6G DX ED VR AF-S

Nikon 18-105VR is the great kit lens supplied on the D90 and is a vast improvement on the 18-55 cheaper kit lens.
Great standard walk-about lens with built in VR (vibration reduction) to stop camera shake.
Takes 67mm filters and it is a good idea to fit a quality UV filter on as soon as possible to avoid any damage to the front element.

Compact, affordable and powerful zoom lens. Features high quality optics designed for use with Nikon DX Format digital SLRs and a 5.8x zoom that delivers superb versatility for a wide variety of shooting situations. Equipped with Nikon’s Vibration Reduction (VR) system and exclusive Silent Wave Motor (SWM), it offers advanced performance in low-light, delivering steady images to both the sensor and viewfinder, and features fast, quiet autofocus.