Grey colours or gray colors are often overlooked by web page designers.  This is a shame, because greys can be very useful.  Especially for a subtle contrast effect for the odd page within a website.  For example, a light grey background for an online order form or an order-form page can be quite an effective choice.

On the right is a greys colour chart©.  Not quite the Fifty Shades Of Grey of literary fame but more shades still than anyone could ever need.  Included are all the named greys, hexadecimal values, RGB numerical values, the eight websafe colours within the grey range, all the half-colour greys, all named greys and a couple of specialist (e-book reader) greys.