Archive Guide Glossary

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There are currently 5 names in this directory beginning with the letter D.
Data Dictionary

A document that explicitly describes metadata structure and rules so that all catalogers input metadata in a catalog consistently. A data dictionary may also specify your controlled vocabularies. Data dictionaries do not contain actual metadata, only the instructions needed to create your metadata.

Data Model

A description of the way that data is structured in a database. It can define what types of things the data describe, what types of data are included in the descriptions, and how different types of things relate to each other.


A copy of a video generated from a master that is usually in a different format and of lower quality than the master. Derivatives can be made for various uses, such as web upload or DVD.

Digital Video

An audiovisual signal that is represented in discrete bits, as opposed to a continuous analog signal. Analog video, such as Hi8 or VHS, is obsolete; all video cameras available today record digital video. Digital video can be tape-based (e.g. miniDV, HDV) or file-based (e.g. .mov, .avi). In this guide, we focus on file-based digital video, as tape-based digital video is mostly obsolete.


To receive data from a remote computer system and save it in a local computer system. The inverse of download is "upload."

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