Video editing software is application software which handles the editing of video sequences on a computer. In the simplest case the video is stored as JPEG image files in a directory. The software typically shows one image on a large area on the screen and a view of the directory. To handle many files in the directory, it is possible to zoom out, so that a single file only covers one pixel line in the editor, or even less, for rough cutting. A play button lets the software automatically advance to the next image, thus playing the video. Additionally JPEG images can be lossless rotated 90 degree or mirrored and hence the editing software also supports this. Of course multiple files at once can be selected for any such operation. In this respect it is very similar to slide show editing software. Like slide show editing software comes with a lot of image file format decoders video editing software comes with a lot of video codec. Video editing software generally also allows for some limited editing of the audio clips which accompany the video, or at least the ability to sync the audio with the video. Video processing in general uses lots of CPU power and moves tons of data on and off the hard disk. There are two different places where you will most feel the benefits of a fast machine and the sluggishness of a slow one: When you render a movie that you have created or write it out to hard disk, you will definitely feel the speed of the machine. On a fast machine, rendering and writing can take minutes. On a slow machine it can take hours. You will learn more about rendering later in this article. A more important issue comes when you are reading data from or writing data to the camera. When the video data stream is coming in from the camera through the FireWire cable, the computer and hard disk must be able to keep up with the camera or the computer will lose frames. When sending a completed movie back to the camera, the processor must be able to stream the data quickly enough or the camera will lose frames. There are many software packages available for editing video on your computer. Windows XP even ships with software that is built into the operating system. Machines from Sony and Apple have software that comes with the machines.