Necessary to save edited pdf?

It's necessary to save it if you want the edits to still be there the next time you open it, yes.

Hi @Cynthia25327390oboo ,

Please use the Adobe Help Center links posted below as a reference:

• https://www.adobe.com/acrobat/hub/how-to/why-wont-pdf-save.html

• https://helpx.adobe.com/acrobat/using/saving-pdfs.html

• https://helpx.adobe.com/in/reader/using/save-view-search-pdfs.html

As for the Adobe Acrobat program saving PDF files automatically to the Adobe Document Cloud,  that is not necessarily a requirement and it can be intructed via Preferences settings how and where to save your work.

However, in my opinion, it is a good habit to save copies of your work automatically to both a Cloud space and also to an external backup media device (or a network drive), other than saving files locally to your computer device only.

Should your computer and its data becomes compromised, or it crashes and the data becomes irrecoverable, this method will always provides the user with data backup redundancy.