Khan Academy is a free online learning platform that offers thousands of interactive exercises, videos, and articles on various subjects. The platform is available to anyone, including students, teachers, homeschoolers, and adults returning to the classroom. Users can learn math, science, economics, finance, grammar, history, government, politics, and more. The platform offers practice exercises, quizzes, and tests with instant feedback and step-by-step hints. Users can also download their favorite content to watch videos offline. The mastery system gives instant feedback and recommendations on which skills and videos to try next, tailored to the user's current learning level.

The platform offers expert-created videos, interactive exercises, and in-depth articles in math, science, economics, humanities, and computer science principles. However, not all functionality is available in the app, such as community discussions, computer programming content, test prep, parent tools, teacher tools, and district tools.

Khan Academy is a 501(c)(3) nonprofit organization with a mission to provide a free, world-class education for anyone, anywhere.

Overall, Khan Academy is a valuable resource for anyone looking to learn something new or sharpen their skills in various subjects.