What is a RELS File Type?
No RELS files should be opened manually. Instead, the file is referenced by Microsoft Office opening the document that contains the RELS file.
If you need to view the information in a RELS file, you can use a text editor since the information is saved in XML format. You should not change the content, however, as this could render the RELS file document unusable.
The relationships within the RELS files are reported at the help of the XML syntax, Id = " Relation, someID ", and lt. Type = relationship Type ". Target = "targetPart; / & gt; where Id is l' single user-defined string, Type is the type of content, and Target is the target file used for the relationship.
With the release of Microsoft Office 2007, OOXML RELS files were introduced for the first time.