The day after Christmas was also the traditional day on which the aristocracy distributed presents (boxes) to servants and employees  a sort of institutionalized Christmas-bonus party. The servants returned home, opened their boxes and had a second Christmas on what became known as Boxing Day.
300 mm. For a 35 mm camera with a diagonal of 43 mm, the most commonly used normal lens is 50 mm, but focal lengths between about 40 and 58 mm are also considered normal. The 50 mm focal length was chosen by Oskar Barnack, the creator of the Leica camera.
Mid-range zoom: This is a lens with a focal length of approximately 18-70mm. You'll probably use it for 75% of your shooting. Luckily, all DSLR makers offer a kit lens in this range, and most discount it heavily if you buy it with the camera. The optical quality is generally very good for the price.