I pulled this from Stack Exchange but thought it would be useful to share

Classic - INSERT:
    ContentVersion          before  insert - no ContentDocumentId
    ContentDocumentLink     before  insert - LinkEntity = current user
    ContentDocumentLink     after   insert - has Id
    ContentVersion          after   insert - has Id, ContentDocumentId
    ContentDocumentLink     before  insert - LinkEntity = object
    ContentVersion          before  update - Publish status changed from R to P
    ContentVersion          after   update - 
    ContentDocumentLink     after   insert - has Id
    
Classic - UPDATE:
    ContentVersion          before  update
    ContentDocument         before  update
    ContentVersion          after   update
    ContentDocument         after   update
    
Classic - DELETE:
    ContentDocument         before  delete
    ContentDocument         after   delete
    
LX - INSERT:
    ContentVersion          before  insert - no ContentDocumentId
    ContentDocument         before  insert
    ContentDocument         after   insert
    ContentDocumentLink     before  insert - LinkEntity = current user
    ContentDocumentLink     before  insert - LinkEntity = object
    ContentDocumentLink     after   insert - LinkEntity = current user
    ContentDocumentLink     after   insert - LinkEntity = object
    ContentDocument         before  update - Publish status changed from U to P
    ContentDocument         after   update
    ContentVersion          after   insert
    
LX - UPDATE:
    ContentVersion          before  update
    ContentDocument         before  update
    ContentDocument         after   update
    ContentVersion          after   update
    
LX - DELETE:
    ContentDocument         before  delete
    ContentDocument         after   delete