In computers and other technology where various storage media are used the term mount refers to making a particular storage device available for use. For example, when you insert a CD-ROM into a Mac, it will read the file structure of the disc, and if it can make sense of it the disc will be mounted. You will see a graphic representation (icon) of it on the desktop signifying it is available for use. Sometimes media must be mounted manually (using special commands or software) even after you insert a disc. This just depends on the format of the media and the configuration of the system.