Metadata, simply put, is data about data.

Imagine an invoice for a purchase your company made. Think of the line items in the invoice as the data. This tells you what particular item was purchased, the quantity, the unit cost, and so on. The metadata will be the stub or the header portion of the invoice. It describes what the line items refer to, who was involved in each transaction, and when each transaction happened.

Examples of metadata are file size, date created, who created it, and description of contents. They give you information on what to expect before accessing the data itself.

Read More about Metadata

So, what is metadata used for? Metadata is useful information for file creators, message recipients, developers, and more. Learn more about it in this post.

A Brief History of Metadata

In 1964, undergraduate computer science major Philip R. Bagley started working on his dissertation where he argued that efforts to “make composite data elements” ultimately rests on the ability to “associate explicitly” to a second and related data element, which “we might term a ‘metadata element.’” While his thesis was rejected, Bagley’s work, including his reference to metadata, was published as a report under contract with the U.S. Air Force Office of Scientific Research in January 1969.

David Griffel and Stuart McIntosh of the Massachusetts Institute of Technology (MIT) Center for International Studies were the first to describe meta data for computer systems in 1967. Meta data back then referred to “statements in an object language about subject descriptions of data and token codes for the data” and “statements in a meta language describing data relationships and transformations and ought/is relations between norm and data.”

In 1969, Jack E. Myers, founder of Metadata Information Partners, now known as “The Metadata Co.,” claimed to have coined the term.

Metadata was traditionally used for card catalogs in libraries until the 1980s. That was before libraries entered catalog data into digital databases.

By 1986, Myers filed a trademark for the unhyphenated word “metadata.”

In the 2000s when data was increasingly stored digitally, digital data was described using metadata. Standards for metadata were also created.

Today, we have unique metadata standards for different disciplines, such as museum collections, digital audio files, and websites. Metadata thus describes the contents and context of data or data files. A web page, for instance, uses metadata to specify what software language it is written in like HyperText Markup Language (HTML), what tools were used to create it, what its subject is, and where to find more information about its subject. In this case, metadata automatically improves reader experience and makes it easier for them to find the page online. On a compact disc (CD), the metadata includes information about the musicians, singers, and songwriters whose work appears on it.

History of Metadata

Government organizations worldwide also routinely store metadata about emails, telephone calls, web pages, video traffic, Internet Protocol (IP) connections, and mobile phone locations.

What Are the Contents of Metadata?

Metadata literally translates to “data about data.” It provides information about one or more aspects of data. As such, it summarizes basic information about data that can make tracking and working with it easier. It usually contains:

  • The means used to create the data
  • The purpose of the data
  • The time and date when the data was created
  • The creator or author of the data
  • The location of the computer network where the data was created
  • The standards used to create the data
  • The quality of the data
  • The source of the data

Here are practical examples.

  • A digital image can have metadata that describes its size, color depth, resolution, when it was created, shutter speed, and other information.
  • A text document’s metadata can include information about its length, who its author is, when it was written, and a short summary of its content.
  • Web page metadata can include a description of its content and keywords linked to this content. This kind of metadata is called a “metatag.”

When metadata is stored in and managed via a database, that database is known as a “metadata registry” or “metadata repository.”

What Are the Types of Metadata?

There are several metadata types. Here are some of them.

Administrative

This type lets administrators impose rules and restrictions governing access and user permissions. That means only users with the right permission and access level can access the data. It also provides information on maintenance and management requirements. It is often used in ongoing research so it includes details, such as the creation date, the file’s size and type, and archiving requirements.

Descriptive

This type identifies specific characteristics of a piece of data. That could be bibliographic data, keywords, song titles, volume numbers, and more. Think along the lines of movie and music collections, books, and office files.

Legal

This type gives users information on creative licensing like copyrights, licensing, and royalties. It helps content and product owners keep track of their intellectual property.

Preservation

This type guides users where to place the data and related items within a hierarchical framework or sequence. It is useful for historical artifacts kept in a museum or priceless paintings.

Process

This type outlines the procedures used to collect and treat statistical data. Hence, it is also known as “statistical metadata.” An example would be a step-by-step guide on data collection and processing used for research.

Provenance

This type is also known as “data lineage.” It tracks the history of a piece of data as it moves throughout an organization. Original documents like the first draft of a manuscript in a publishing company would be an example. It is useful for ensuring data governance.

Structural

This type reveals how different elements of a dataset are assembled. It is often used for digital media content. It can, for instance, describe how the pages in an audiobook should be organized to form a chapter, and how chapters should be organized to form volumes, and so on.

Use

This type is useful for analyses. Examples would include the information attached to trends in customer behavior.

What Are the Uses of Metadata?

Metadata has several uses and we named some of them below.

Tracking File Changes

Most if not all computer files (e.g., documents, images, videos, and audio files) have embedded metadata. While this information is automatically added by authoring apps (e.g., Microsoft Office, Adobe Illustrator, etc.), users can also add them manually. File metadata is useful for tracking changes made to files, especially if it includes version information like when the file was last modified, on what computer, and by who.

Organizing and Finding Files

Users can also use metadata to organize files with the help of keywords. They can also utilize filters if they need to analyze specific sets of photos and create selections based on criteria like ratings or capture times. Some devices with geolocation capabilities include the locations where photos and videos were taken. This also makes it easier for other users to search for files using specific keywords.

Proving Intellectual Property Ownership

Metadata may be written into digital photos to identify who owns them. It can be used to copyright photos. This information includes contact information, camera brand or model, exposure information (e.g., shutter speed, f-stop, etc.), and descriptive information like keywords. All this data makes images searchable on computers and the Internet.

Some cameras automatically create other metadata like color space, color channels, exposure time, and aperture. Others can be inputted by the photographer and software after the photos are downloaded to a computer.

Tracking Suspects and Persons of Interest

Videos from traffic cameras are particularly useful for law enforcement agents using automatic number plate recognition and vehicle recognition identification software to track and monitor license plate data to create reports and alerts or find suspects or persons of interest in criminal cases. As with photos, some of this data is automatically added by the cameras, computers, and other systems used. Others like keywords and descriptions can be added by the video creators.

Monitoring Phone Calls and Messages

Information on the times, origins, and destinations of phone calls, electronic messages, instant messages, and other modes of communication is another type of metadata. Apart from personally tracking them to check bills, law enforcers also use them to track persons of interest in investigations.

Tracing Geographic Locations

Geospatial metadata is related to geographic information system (GIS) files, maps, images, and other location-based data. This is useful in documenting the characteristics and attributes of geographic data like database files and GIS data. It includes details, such as who developed the data, when it was collected, how it was processed, and what formats it comes in. For photos and videos, it helps with identifying locations for documentation in a scrapbook, for instance.

Uses of Metadata

Who Manages Metadata?

Determining who manages metadata depends where it is stored—internally or externally. But first, let’s tackle what metadata management is.

What Is Metadata Management?

Metadata management refers to the policies and processes used to manage data about data. This kind of governance involves developing standards, policies, and best practices applied to data assets wherever they go. Now, let’s move on to who is responsible for the process.

Metadata Management Types

Internal

Metadata stored internally or in the same file or structure as the data means the metadata always travels as part of the data it describes. As such, the information is always available with the data and can be manipulated locally. This method creates redundancy and does not allow managing all the metadata in one place. But, it can increase consistency since the metadata is readily changed whenever the data is changed.

External

Metadata that is saved in a separate file or field from the data it describes is typically stored in a data repository. It allows collocating metadata for all of the repository’s contents. An example would be files in a database that have been cataloged for more efficient searching and management. This also applies to data stored in data warehouses. Unlike internal metadata, the division of the metadata from files, especially standalone ones, increases misalignments between the two since changes to either may not be reflected in the other.

Why Does Data Management Matter?

Employing a good strategy to manage metadata can benefit your organization. Here’s why.

Makes Data More Accessible

Well-structured metadata lets information technology (IT) teams locate and retrieve the data they need fast, reducing downtime and increasing productivity. This is especially critical for large organizations that store data in multiple systems and data platforms.

Supports Data Governance

Data governance is important for organizations who wish to maintain data quality, compliance, and cybersecurity. Metadata management provides detailed records of data origins, usage, and ownership. This transparency is a must for regulatory compliance and ensuring that data is used ethically and responsibly. It also enables data quality control, allowing users to to track changes or updates made to the data. The additional context also lets data engineers better understand the data and where it should belong.

Streamlines Data Integration

Integrating data from various sources is common in interconnected business environments. Metadata acts as a bridge between disparate data systems, enabling seamless data integration. Proper metadata management helps support integration efforts by easing mapping to business intelligence (BI) tools, data catalogs, and data governance tools.

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Just like any catalog system that helps users locate books efficiently, metadata helps users organize and retrieve data quickly within a database.

Key Takeaways

  • What is metadata? Metadata is data about data.
  • While Myers filed a trademark for the unhyphenated word “metadata” in 1986, others have used the term before him.
  • The different metadata types are administrative, descriptive, legal, preservation, process, provenance, structural, and use.
  • What is metadata used for? It can aid users in tracking file changes, organizing files, proving intellectual property ownership, and more.
  • Metadata management refers to the policies and processes used to manage data about data. It is critical for organizations that store data in multiple systems and even physical locations.

Sources

  • https://www.splunk.com/en_us/blog/learn/metadata-management.html
  • https://en.wikipedia.org/wiki/Metadata
  • https://www.netsuite.com/portal/resource/articles/data-warehouse/metadata-management.shtml