Quizlet Flashcards API has over seven million flashcard sets and about two million registered users. The API allows programmers to utilize more than two hundred million flashcards database which covers virtually every subject. It allows users to download, scan, submit, and modify flashcard sets, scan for definitions, create, update, and enter groups, mark sets as favorites, and more.
The API uses RESTful calls and responses are formatted in JSON. Quizlet's API also suppors OAuth2 which allows developer to authenticate and act on behalf of Quizlet users.
An API is an intermediary between the developer and the system server. The developer requests the server regarding what he/she is in need of through an API. Then, the server will process the request and send back the data or service through the API. The Quizlet API lets developers use Quizlet's vast database of over 200 million flashcards covering every possible subject.