Update introduction.md

docs.it4i/karolina/introduction.md

@@ -6,7 +6,7 @@ Nodes are interconnected through a fully non-blocking fat-tree InfiniBand networ
 
 The cluster runs with an operating system compatible with the Red Hat [Linux family][a]. We have installed a wide range of software packages targeted at different scientific domains. These packages are accessible via the [modules environment][2].
 
-The user data shared file-system and job data shared file-system are available to users.
+The user data shared file system and job data shared file-system are available to users.
 
 The [PBS Professional Open Source Project][b] workload manager provides [computing resources allocations and job execution][3].