Google Classroom is a free blended learning platform developed by Google for educational institutions that aims to simplify creating, distributing, and grading assignments. The primary purpose of Google Classroom is to streamline the process of sharing files between teachers and students. As of 2021, approximately 150 million users use Google Classroom. Google Classroom uses a variety of proprietary user applications (Google Applications for Education) with the goal of managing student and teacher communication. Students can be invited to join a class through a private code or be imported automatically from a school domain. Each class creates a separate folder in the respective user's Google Drive, where the student can submit work to be graded by a teacher. Teachers can monitor each student's progress by reviewing the revision history of a document, and, after being graded, teachers can return work along with comments and grades. History Google Classroom has undergone a series of updates and changes since its original release in May 2014. Features Google Classroom integrates several Google Applications for Education, such as Google Drive, Google Docs, Google Sheets, Google Slides, Google Forms, Google Sites, and Gmail.A Google Calendar integration was later added to the platform. Students can be invited to classrooms through the institution's database, through a private code that can then be added in the student's user interface, or automatically imported from a school domain. Each class created with Google Classroom creates a separate folder in the respective user's Google Drive, where the student can submit work to be graded by a teacher. Assignments Assignments are stored and graded on Google's document applications. Rather than sharing documents that reside on the student's Google Drive with the teacher, files are hosted on the student's Drive and then submitted for grading. Teachers on Google Classroom have the option of creating Assignments in various templates and formats with different accessibility options, such as permissions to view, edit, and comment. These assignments can be submitted for a grade and allow the teacher to provide feedback. Students may also attach additional documents from their Drive to their assignment. Grading Google Classroom supports different grading schemes. Turned in assignments can be graded by teachers and returned with comments before the final submission, allowing for the students to modify their work. Once turned in, assignments can only be edited by the teacher. Communication Announcements can be posted by teachers to a "class stream" which can