Is this a standard file Mac/private/var/root ( root being one of 6 with a red circle in the lower right hand corner with a minus sign in it.)
The red circle with dash or a minus sign in it refers to a folder to which you do not have permissions to see the contents of. The folder you are specifically showing in that screenshot are System files owned by the root/system. You shouldn't attempt to modify, move or delete these files as they are important to your operating system and that is why the permission has been set. 

To answer your question, yes it's completely normal, it's likely that its just logging errors, system activity or even a programs activities, it's nothing that you need to be worried about, it's just standard system operations.