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 to 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