Subject headings are standardized terms used in libraries and databases to categorize and organize information. They help users find materials on specific topics quickly and efficiently. For example, a subject heading like Environmental Science can lead to books, articles, and other resources related to that field. These headings are often part of a controlled vocabulary, meaning they are predetermined and consistently used across various platforms. This consistency allows researchers and students to locate relevant information without confusion. For instance, searching for Climate Change as a subject heading will yield focused results on that particular issue.