Updated Introduction (markdown)

Introduction.md

@@ -88,11 +88,7 @@ Official terminology of ReCodEx which will be used in documentation and within c
 
 * **Judge** -- Judge is a standalone comparision program which compares sample outputs against output from tested program.
 
-* **Limits** -- Tasks executing external programs are usually executed in sandbox, to limit these programs predefined limits are used. These limits are specified in job configuration and can limit execution time, consumed memory, used disk space and some other worth-to-watch values.
+* **Limits** -- Tasks executing external programs are usually executed in sandbox with defined limits on run time, consumed memory, used disk space and others. These limits are specified in job configuration. The term _limits_ in this context means all the restrictions together.
-
-// TODO: which one, the above or the below?
-
-Tasks executing external programs are usually using sandbox with defined limits on run time, consumed memory, used disk space and others. The term 'limits' in this context means all these restrictions for program execution together.
 
 * **Hwgroup** -- Hardware group is set of workers with similar hardware capabilities. Each group has unique string identifier and every worker in particular group has that identifier inside its configuration. Hardware group management is done manually by system administrator. Jobs are routed to the workers according to hwgroup, limits are also tied up with specific hwgroup.