A hardware upgrade is any new hardware that replaces or adds to old hardware in the computer. A good example of a common hardware upgrade is a RAM upgrade, where the user is increasing the computers total memory, which will increase its overall speed and efficiency. Another good example is doing a video card upgrade, which is the act of removing th...e old video card and replacing it with a new video card that is much more capable than the previously installed video card, again increasing the capabilities of the computer.
Hardware is best described as a device that is physically connected to your computer or something that can be physically touched. A CD-ROM, Monitor, Printer, and video card are all examples of computer hardware. Without any hardware your computer would not exist and software would have nothing to run on. The image to the right is of a webcam, an example of an external hardware peripheral that allows users to make videos or pictures and transmit them over the Internet.