Technology and the babe

This is conversation Isaac and I had yesterday...

I: Mommy what are you doing?
Me: I'm checking my e-mail?
I: What's a e-mail?
Me: Well, I type a note on my computer, and then I send it to Miss Jennie's computer. Then she reads it on her computer.
I: (looking all around and under our computer) Where is Miss Jennie's computer?
Me: At her house.
I: Where is the e-mail?

So we went on like this for awhile. How do you explain the Internet to a 2 1/2 year old?