Do I need to keep my physical W-2, 1099, etc., if I have scanned them and saved them to my computer?

I always e-file my returns, and I'm trying to go paperless but want to confirm:

  1. Do I need to retain physical paper copies of my W-2, 1099, receipts, or any other tax related documents after filing my return, or is scanning them to my computer okay?

  2. Is the answer to the above true for everything, such as personal income, self-employed income, LLC documents, etc.? Ultimately if I don't have to keep any paper at all for the IRS, that'd be the ideal goal.