rephrase intro

User-documentation.md

@@ -1,6 +1,4 @@
-# User Documentation
-
-**This documentation is currently obsolete and in much need of revisions. Please stand by for updates...**
+# User Documentation - OUTDATED
 
 **If you are a ReCodEx user and you wish to contribute, please, let us know...**
 
@@ -11,12 +9,11 @@ and local storage are used. Also a decent JavaScript runtime must be provided by
 the browser.
 
 Supported and tested browsers are: Firefox 50+, Chrome 55+, Opera 42+ and Edge
-13+. Mobile devices often have problems with internationalization and possibly
+13+. Mobile devices can have problems with internationalization and possibly
 lack support for some common features of desktop browsers. In this stage of
 development is not possible for us to fine tune the interface for major mobile
 browsers on all mobile platforms. However, it is confirmed to work with latest
-Google Chrome and Gello browser on Android 7.1+. Issues have been reported with
-Firefox that will be fixed in the future. Also, it is confirmed to work with
+Google Chrome, Firefox and Gello browser. Also, it is confirmed to work with
 Safari browser on iOS 10.
 
 Usage of the web application is divided into sections concerning particular user
@@ -33,16 +30,16 @@ privileged users. Described roles are:
 ## Terminology
 
 **Instance** -- Represents a university, company or some other organization
- unit. Multiple instances can exist in a single ReCodEx installation.
+ unit which uses ReCodEx.
 
 **Group** -- A group of students to which exercises are assigned by a
- supervisor. It should typically correspond with a real world lab group.
+ supervisor. It should typically correspond with a real world lecture or lab group.
 
 **User** -- A person that interacts with the system using the web interface (or
  an alternative client).
 
 **Student** -- A user with least privileges who is subscribed to some groups and
- submits solutions to exercise assignments.
+ can submit solutions to exercise assignments.
 
 **Supervisor** -- A person responsible for assigning exercises to a group and
  reviewing submissions.
@@ -50,10 +47,11 @@ privileged users. Described roles are:
 **Admin** -- A person responsible for the maintenance of the system and fixing
  problems supervisors cannot solve.
 
-**Exercise** -- An algorithmic problem that can be assigned to a group.  They
+**Exercise** -- An algorithmic problem that can be assigned to a group. They
  can be shared by the teachers using an exercise database in ReCodEx.
 
 **Assignment** -- An exercise assigned to a group, possibly with modifications.
+ In more detail it is full copy of exercise.
 
 **Runtime environment** -- Runtime environment is unique combination of platform
  (OS) and programming language runtime/compiler in specific version. Runtime
@@ -62,7 +60,7 @@ privileged users. Described roles are:
 
 **Hardware group** -- Hardware group is a set of workers with similar hardware.
  Its purpose is to group workers that are likely to run a program using the same
- amount of resources. Hardware groups are managed byt the system administrators
+ amount of resources. Hardware groups are managed by the system administrators
  who have to keep them up-to-date.
 
 ## General Basics