How can I explain the concept of a blog to my dad?

[Jacob]

My dad is 44 years old. He doesn't have a blog, doesn't read a blog, doesn't even know what a blog is. Therefore, he was quite confused when I mentioned the fact that I would be updating my blog tomorrow. I know what a blog is (obviously, I've got one). But how can I explain it to my dad? I just can't seem to find the right words. Thanks for your help, God bless!
Timothy S - OMG. That's great! He's a huge Star Trek fan, thanks for the help!

[Dominic]

Tell him it's an online journal or diary and he'll understand.

– Dominic

[Timothy S]

How's his Star Trek? Tell him it's like the Captain's log.

[Matthew]

I don't know why you bring your Dad's age into this because that really has nothing to do with the issue. Anyway, if you really want him to understand, why don't you SHOW him what a blog is? If you explain "blog" to him as an online journal, he may get nervous as to what you may be writing about. If you show him your blog, his mind will be set at ease that you aren't writing about anything inappropriate that others can read.

If he's a big Star Trek fan, you could also show him George Takei's blog? (http://www.georgetakei.com/)