Mas-System folder showing a reports folder underneath

I have a "reports" folder showing underneath my Mas_System folder. 

It contains a report underneath each of the following headings:  AP_checkhistoryreport, AR_Customerlisting, GL_Detailreport, SO_Backorderreport.

I thought customized forms were placed underneath the specific company and then underneath its "reports" folder, then by the above headings.  Why are there only these few underneath this Mas_System folder?

Note:  these same headings & their related reports are found underneath each of my companies directories, underneath the "reports" folder within those companies.

Thanks, Shelby.... trying to clean up reports prior to version 4.5 upgrade.