What is the difference between REPLY and REPLY ALL?
If you receive an e-mail that was sent to you and several other people, you can reply either to just the person who sent it, or to the person who sent it as well as everyone else who received it. For example, say your sister sends an e-mail to you and your two brothers, asking if you will be attending the family reunion this summer. If you want to let her, and only her, know your plans, then click on “Reply” and send your message. If you want her and your two brothers to know your plans, click on “Reply All” and send your message.