Media comes in a variety of file types, so when you are looking for, or creating your own media, you must consider what the hardware and software requirements will be for viewing the resource. New computers usually have the capability of displaying most media formats, but there are often software viewers or plugins required to help. This is particularly true for video files that are often very platform specific such as Apple’s Quicktime mov file type or Microsoft’s Windows Media Video or wmv. Each type can be viewed on a Mac or a PC, but extra software components will be needed on the respective platform. If you want to put video on a mobile device such as an iPhone or iPod, then you need to find out what the compatible video file format is. In the case of an iPod it is m4v or mp4. If you want to embed a video in a Web page or blog posting, then you need to figure out what file type is best optimized for doing that while keeping in mind the file size and the implications on the amount of time for downloading and viewing. Flash (.flv or .swf) can be easily played by all computers that have the Flash player installed (common on most systems), but it cannot be played on an iPhone, iPod Touch or iPad.
If you are purchasing a video camera for your classroom, then you will want to make sure that the video format that the camera encodes in is compatible with your computer platform and the software you have. There is no doubt that you can do a conversion to a format that is compatible, but that just adds another time consuming step to the process.