A Search API is a set of programming instructions that allows developers to integrate search functionality into their applications. It enables users to query a database or a collection of data and retrieve relevant results based on their input. This is commonly used in websites and applications to help users find information quickly and efficiently. Search APIs can support various features, such as filtering, sorting, and pagination, enhancing the user experience. Popular examples include the Google Search API and the Elasticsearch API, which provide powerful tools for searching large datasets and improving the accessibility of information.