A course has the following properties.
It is a grouping of students who are taught as a logical group.
It can have one or more teachers/instructors.
You can add projects, modules or resources to it that can include Assessments allowing you to assess how well the students are grasping the subject matter
You can instantly access student code and projects.
You can clone an existing course to a new course
You can integrate the course with any LTI enabled LMS platform such as Canvas, D2L, Moodle, Blackboard and many others. Your LMS can auto-populate courses and grade data can be fed back from Codio to the LMS.
You can run Plagiarism detection against the students work to allow to check for code copying and potential cases of cheating between members of a course. With the current version, Codio will compare the code projects of all students within a course for a specific teaching assignment.
And much more. For more detail, check out our documentation here