[Doc] Define the user roles

docs/source/req/index.rst

@@ -6,5 +6,6 @@ This section concerns requirements for the system-to-be.
 .. toctree::
    :maxdepth: 2
 
+   users
    use-case/index
    suppl-spec

docs/source/req/users.rst

@@ -0,0 +1,50 @@
+Types of Users
+==============
+
+Firstly, to understand which use cases that need to be implemented,
+we analyzed which types of users there are and how they interact
+with our system.
+
+The primary users are **students** and their **supervisors**.
+They can interact quite similarly with the system:
+
+- Create a new project
+- Edit public information about a project
+- Invite new members to a project
+- Create new tasks
+- Evaluate the tasks
+
+However, there are differences between what students and supervisors can do.
+Unlike supervisors, students are not allowed to evaluate the project.
+On the other hand, supervisors should not be able to do tasks nor to upload
+project reports and slides while students can do those tasks.
+
+After the students submit the reports, there will be **judges**
+whose responsibility is to assess these reports.  They also evaluate
+the groups' project oral defense (also called *presentation*).
+They should therefore be allowed to access and evaluate
+reports and slides of projects they are assigned.
+
+During the process, **academic assistants** of each faculties should collect
+statistical reports of each project and print the results of the subject.
+
+The system's user categories can be summarized in the table below
+
+.. tabularcolumns:: |l|L|L|
+
+==========  =========================  ===============================
+Type        Responsibility             Ability                        
+==========  =========================  ===============================
+Student     progress the project       manage projects,               
+                                       manage and complete tasks,     
+                                       upload reports and slides      
+Supervisor  support the group and      create tasks, evaluate projects
+            evaluate the project                                      
+Judge       evaluate groups'           access and evaluate            
+            reports and presentations  reports and presentation       
+Assistant   collect statistical        aggregate and export           
+            report and evaluation      projects' evaluation           
+==========  =========================  ===============================
+
+In the system, we assigned users of each group a role: ``student``,
+``supervisor``, ``assistant``, ``judge``.