Remember those? Pieces of paper, carefully selected or written on the nearest stack of clean sheets you can get your hands on? Boy, them were the days.
I had an acquaintance once who used to write me the longest letters on paper that seemed a crime to use. It was usually the handmade looking stuff - rough in texture and the color of old memories. Opening a letter from him was like Christmas. I couldn't wait to unfold the treasure in my fingers, that I knew he had written for me with a steady hand that was the voice of his thoughts. And I'd read the letter, over and over, just to feel its weight and linger on the words that lay on that great ivory landscape citied by his hurried paragraphs.
Reading an email is not the same. You see words on a background that never changes, and you have no way of sensing the person who isn't present to talk to you in person. A letter tells you that the person took care to fold it carefully before inserting it into the envelope, addressed by the same focused hand that composed the letter. A letter says they were thinking of you for a long time, enough to spend a good part of the day to put it together and send it off.
Though they may say the same thing, a letter is an entirely different animal than an email. Of course it is: one breathes, and the other does not.