Metadata

- Overview

Metadata is "data about data," providing structured information that describes, explains, or locates information, making it easier to retrieve, manage, and use. It enhances searchability (keywords, dates), provides context (author, file type), and aids in data management. Key types include descriptive, structural, and administrative.

1. Types of Metadata:

• Descriptive Metadata: Identifies and describes resources (e.g., title, author, keywords).
• Structural Metadata: Explains how data is organized, such as how pages are ordered to form a chapter.
• Administrative Metadata:  Technical information about files, including creation date, file type, and permissions.
• Provenance Metadata: Tracks the origin and history of data, often called data lineage.

2. Purpose and Benefits of Metadata: 

• Searchability: Enables faster retrieval of data by acting as tags or descriptors.
• Management: Facilitates tracking, organizing, and maintaining data resources.
• Context: Retains information about how data was created, used, and stored, which is essential for validation and reuse.
• Interoperability: Facilitates sharing of information across systems.

3. How to Create Metadata: 

Metadata can be created manually by users (tagging, descriptions) or automatically by systems (EXIF data on photos, file creation timestamps). It is best practice to generate metadata throughout the data lifecycle, such as via data dictionaries or Readme files.

4. Use in Databases and Data Management: 

• Database Management: Technical metadata defines schemas, table names, data types, and column constraints.
• Data Governance: Uses metadata to classify data sensitivity (e.g., PII), track ownership, and manage compliance.
• Operational Management: Tracks data flow and system processes.

Please refer to the following for more information:

• Wikipedia: Metadata

- Examples

The prefix “meta” typically means “an underlying definition or description” in technology circles. In the 21st century, metadata typically refers to digital forms, but traditional card catalogs contain metadata, with cards holding information about books in a library (author, title, subject, etc.).

Metadata makes finding and working with data easier – allowing the user to sort or locate specific documents. Some examples of basic metadata are author, date created, date modified, and file size. Metadata is also used for unstructured data such as images, video, web pages, spreadsheets, etc. 

Web pages often include metadata in the form of meta tags. Description and keywords meta tags are commonly used to describe content within a web page. Search engines can use this data to help understand the content within a page. 

- Manual and Automated Metadata Creation

Metadata can be created manually or through automation. Accuracy is increased using manual creation as it allows the user to input relevant information. Automated metadata creation can be more elementary, usually only displaying basic information such as file size, file extension, when the file was created, for example. 

Metadata can be stored and managed in a database, however, without context, it may be impossible to identify metadata just by looking at it. Metadata is useful in managing unstructured data since it provides a common framework to identify and classify a variety of data including videos, audios, genomics data, seismic data, user data, documents, logs.