Glossary - D A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Digital Camera This input device is similar to a normal camera but takes the photos without using film. The photographs can be transferred to a computer for editing. Directory Tree Directory tree A way of organising files so that they are stored inside directories. DVD Digital Versatile Disc. This is an optical disk which can store about 4.5Gb of data. DVD-ROMs are usually used for storing films on.