Archive Guide Glossary

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There are currently 38 names in this directory
API (Application Programming Interface)

A protocol that specifies a way for a software application to communicate and integrate with a program that provides a service. Google provides APIs, for example, so that people can use its data, such as location data from Google Maps or video data from YouTube, in their applications.


A copy of data, stored in a secondary location, which is used to restore data in the primary storage location that is corrupted or lost. Restoring involves copying data from the backup to the primary storage to replace the corrupted or lost files. Backing up is a storage strategy that allows you to recover from data loss.


See “Hash Value”

CLI (Command-Line Interface)

A way of interacting with a computer program which involves typing lines of text in a command-line shell. Some programs are only available with command-line interfaces, which facilitate their automation and use in programming scripts. However, command-line interfaces can be harder for casual computer users to interact with than graphical user interfaces (GUI), which use windows, icons, menus, and pointers.


A codec is software that can encode/compress and decode/decompress digital files, including video files. Common video codecs include H.264/MPEG-4 AVC, MPEG-2, and DV. A video stream can be encoded with one of these codecs and contained in a file format like AVI or Quicktime.


A legal protection intended to give the creator of original work exclusive rights to their work for a designated length of time. It gives the creator the exclusive right to copy, use, adapt, show, and distribute their own work, and the right to determine who else can copy, use, adapt, show, and distribute the work.

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."

EDL (Edit Decision List)

A document used in video post-production that contains a list of clips used in an edited video. EDLs originate from older film and video workflows when editing was a two stage process. Today, they can be used to move editing projects from one software or system to another. EDLs also provide useful documentation, showing what source files were used to create an edited video.

Embedded Metadata

Metadata that is stored within the digital object it describes. Some embedded metadata, such as file size, are essential to the functioning of the file, and are always written to the file by the device or software system. Other embedded metadata are non-essential and can be optionally added (e.g. rights information). Embedded metadata is not guaranteed to be accurate—for example, if your camera is set to the wrong date. Embedded metadata stay with the digital object as long as the object is intact, but can be intentionally stripped or altered. Embedded metadata can be lost if a file is transcoded to another format.


The process of encoding your files using a cryptographic algorithm so that only authorized parties with a “key” (e.g. a password) can decrypt them. The two main types of encryption are symmetric-key and public-key. Symmetric-key encryption uses the same key, or password, to encrypt and decrypt information. Public-key encryption uses one key to encrypt, and a different one to decrypt, and is more secure.


In data models, an entity is any "thing" that is identified and described with data. For example, if a database keeps track of the model, year, and license plates of all the cars in a sales lot, each car is an entity.


A computer file system developed by Microsoft that can be read and written to by Mac and Windows devices. Many USB flash drives come formatted as FAT32. The maximum file size on a FAT32-formatted volume is 4GB, which may not meet the needs of large video files.

File Format

The specification by which a digital file is encoded. Some file formats are designed to store particular kinds of data while others are more like containers that can hold many kinds of data. Common video file formats like Quicktime (.mov), AVI, and mp4 are container formats that contain video and audio streams, metadata, subtitle tracks, etc.

Finding Aid

A document that contains information about a specific collection within an archive. It is a simple way for users to determine if the content in a collection is relevant to their research. The structure of finding aids differ depending on the material being described; they can contain detailed content lists, a description of the scope of the collection, biographical and historical information, and even restrictions on use or access to the content.


An interface standard for transferring data between digital devices, especially audio and video equipment. Developed by Apple in the 1990s, FireWire is becoming obsolete.

FTP (File Transfer Protocol)

A network protocol for transferring files between two points over the Internet. Users use FTP client applications (e.g. FileZilla) to communicate with an FTP server.

GUI (Graphical User Interface)

A way of interacting with a computer program that involves using windows, icons, menus, and pointers. Most computer users are familiar with graphical user interfaces. GUIs can be easier for casual users to interact with than command-line interfaces (CLI), which require commands to be typed as lines of text.

Hash Function

An algorithm that computes a hash value or checksum from any set of data, like a file. Common hash functions include MD5 and SHA1. Hash functions are used to check file integrity and for security purposes.

Hash Value

The string of alphanumeric characters that results from running a hash function algorithm on data or a file.  The hash value of a file will always remain the same as long as the file is unchanged, so it can be used to identify altered, corrupted, and duplicated files.


A computer file system developed by Apple that can only be read by Windows devices using special software. Windows devices cannot write to HFS-formatted volumes.

Intellectual Property

A legal concept that refers to creative works for which exclusive rights are recognized. Common types of IP rights include copyright, trademarks and patents.


A term derived from "malicious software," and that refers to all computer viruses, worms, Trojans, and spyware.

Metadata Standard

A published document that describes how to create, use, and interpret metadata in a specific domain or for a specific purpose, which is intended to establish a common understanding among its users. A metadata standard defines the structure and meaning of its acceptable data elements, rules, and values. Many communities, including broadcasters, social scientists, and art museums, publish metadata standards to meet their descriptive needs.

NAS (Network Attached Storage)

Computer data storage that is accessed through a network. A NAS appliance is a computer that is specially designed to store and serve files over a network.


A computer file system developed by Microsoft that is read-only on Macs. Macs can write to NTFS-formatted volumes only with special software.


To copy media from a camera or memory card to a storage device connected to a computer.


A unit of measure for data. One petabyte (PB) is equivalent to 1,000 terabytes (TB), or 1,000,000 gigabytes (GB).


A system that acquires, stores, monitors, preserves, and provides access to its resources, run by an organization committed to providing long-term access to authenticated content to its users. A repository requires significant infrastructure to build and maintain.

RAID (Redundant Array of Independent (or Inexpensive) Disks)

A storage technology that combines multiple hard drives together to provide fault tolerance and better performance. Data is spread out across the drives, along with additional calculated data, so that data can be re-generated if part of the array fails. RAID protects you against data loss in the case of hardware failure. Unlike backup, RAID does not offer protection against file corruption or deletion, or data loss to malware, theft, or natural disaster.


A system that acquires, stores, monitors, preserves, and provides access to its resources, run by an organization committed to providing long-term access to authenticated content to its users. A repository requires significant infrastructure to build and maintain.

SAN (Storage Area Network)

A dedicated network of storage devices shared among multiple servers, designed for fast access and large data transfers.


The process of ensuring that computer files in one location are copied to one or more other locations on a regular basis. Synchronization is also referred to as mirroring or replication. Unlike backup, synchronization does not allow you to go "back in time" to recover lost or altered files.


To re-encode a digital file to a different encoding scheme, such as converting an H.264/MPEG-4 AVC video to Apple ProRes. Transcoding is usually done when a video’s encoding is not supported by the system that needs to use it. Transcoding fundamentally alters the file, although lossless methods can allow the original data to be reconstructed from the transcoded data.


To send data from a local computer system to a remote one. The inverse of upload is "download."

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