Hi Granny!! Welcome to DN~
I've looked at your Profile, and see that you've left comments on Wallpapers, so I think you're asking about answering or leaving a greeting on their Profilepage. If you click on their username in the comment they left you, it will take you to their page. There, you can write the comment and Send. While there, you can click on Wallpapers and see everything that member has uploaded. When you're familiar with the site, we'll talk about how you can leave 'picture' greetings for your new friends!! Have you been to the Homepage and looked through our different categories?? Let me know if I can help!

Oh, and you can write to them using PM..Private Messages. Click on the 'Contact Member' tab on their Profilepages. Look for the Envelope at the top of your page to see if you have mail, and you can write back to them under their note to you.