There are a few issues that a computer owner might run into when the machine decides to start showing error messages and while some issues cannot be fixed without a professional's help for computer repair, something like when the computer won't turn on or when a "blue screen of death" pops up on the screen, there are several standard definitions for the numbers that will appear on the screen. Knowing what these numbers mean can be a great help to understanding what's wrong with a computer and they can also help speed the repair process when a computer is taken into a shop.

Although the photographic techniques used today in applications that range from some consumer entertainment to a complex business vision system, very often employ advanced digital techniques and recording, the earliest photographs actually took fifteen minutes to take and required that human subjects be situated in a vice-like grip for the duration of the photograph taking sequence. Fairly standard portrait photographic techniques had been devised by the 1840s although the first ever portrait was taken in 1938 when an early photographer took a picture of himself. The first photographs ever taken were by a French inventor named Joseph Nicéphore Niépce.