Manager	Managers can access course and modify them, they usually do not participate in courses.
Course creator	Course creators can create new courses.
Non-editing teacher	Non-editing teacher can not change content in a course, but can see the results and evaluate students in a course.
Student	Students generally have fewer privileges within a course.
Guest	Guests have minimal privileges and usually can not enter text anywhere.
Teachers	Teachers can do anything within a course, including changing the activities and grading students.
Company Manager	Company Manages individual companies - can upload users etc.
Company Department Manager	Manages departments within companies - can upload users etc.

As a manager you cant assign all rolls. 
Go to the "Administration" block and navigate to: Course administration / Users / Enrolled users.

The Manager role enables users assigned the role to access courses and modify them in the Company assigned. There have , as well as perform certain administrative level tasks related to courses, users, grade settings, etc.

The course creator can (as the name suggests!) create a course. If the setting "Creators' role in new courses" is left as default (teacher), then the course creator is enrolled as a teacher in the course they have just created and can then edit the course settings and enrol other users.

A non-editing teacher is able within a course to view and grade students' work but may not alter or delete any of the activities or resources. This role might typically be given to a classroom assistant for example.

A user with the Student role in Growdly can participate in course activities and view resources but not alter them or see the class gradebook. They can see their own grades if the teacher has allowed this. When a student first joins Growdly they see all available courses. Once they have enrolled or been enrolled into at least one course they then only see their own courses in the My Courses section of the navigation block or via the My home link. A student's view and navigation in Growdly will be different from the course teacher's or from students assigned to a different group.
Manager and Teachers determine how a student enrolls, and what they can do or see in a Growdly site.

Growdly has a built-in "Guest account". Visitors can log in as guests using the "Login as a guest" button on the login screen and enter any courses which allow guest access. In addition, logged-in users can enter any courses which allow guest access without being required to enrol. Guests ALWAYS have "read-only" access - meaning they can't leave any posts or otherwise mess up the course for real students.

Teachers can do almost anything within a course, including adding or changing the activities and grading students. Teachers can only teach in the courses they have been enrolled in.

Company Manager cant edit the company, manage departments, assign department users/managers, make optional profiles and assign users to the company.  User management in clouds: Create user, edit users and upload Users. The Company Manager cant also also manages Courses: Assign them to the company, make user enrolments, create course, manage company course settings and teaching locations.

Company Department Manager cant do the same as a Company Manager but only in a department.