How to handle duplicate .module files that live in 2 places? I have not used Drupal before and have been thrown a project to fix up some things.

But I noticed the file I need to edit lives in two places:


one in includes/jobs.module.
another one in sites/all/modules/jobs/jobs.module.


Is one meant to be a sym link of the other or something? As this is not the case in the project I have been given. What file should I be editing? 

I'm sure this is basic stuff for and Drupal dev. An suggetions?
There shouldn't be a job.module in the includes directory at all, your module files for your job module should all be in sites/all/modules/jobs.

You generally shouldn't put anything in (or modify anything in) the includes directory or you will make it harder for yourself to upgrade drupal core in future.

I would say you should:


check for any differences between the two files.
If they are different determine whether or not anything in includes/jobs.module should be in sites/all/modules/jobs/jobs.module. If so add it.
Delete includes/jobs.module