What is the files object in salesforce?
Which object stores the files (not attachments)? I'm looking to access this via a trigger. Is it possible to add a field to these document/file objects?
The files object in salesforce is -
The actual "content" of the file is saved as a ContentVersion
ContentVersion can have custom fields
ContentVersion is a child of ContentDocument - an object implicitly created by SFDC when the first ContentVersion is created for that file. Subsequent file versions are saved as the 2nd, 3rd, ... children of ContentDocument You can think of ContentDocument as a 'header' for all of the versions of that document.
ContentDocument (and thus, the latest ContentVersion) is connected to the target object from whence the original file was uploaded via ContentDocumentLink (e.g. a link between Opportunity and ContentDocument)