The two links will be different so be conscience of which you wish to share. In order for any changes to take effect and go live, you will have to publish your document.
Preview links will show the current state of your document, think of it like a "draft". This is especially useful if it's currently being edited or still in progress. Sending someone a preview link will not require them to sign in to AirMason. You can continue to make edits until you are ready to hit publish.
Published links will showcase the latest state of your document, think of it like the "live version". You will be able to see the page animations, special effects, transitions, etc in this link. When publishing, there is a formal process that prompts you to notify employees or not.