To blog or not to blog!

I still don't understand how people who blog write some personal information about themselves and publish the URL of the blog everywhere. It is unsafe if someone gained so much information about you. Imagine for example someone who wants to deceive people in some email by representing himself as you and confirming that with some information he got from your blog. Yeah, it is the Conspiracy Theory. But it might be true. Imagine also one who is collecting information about your personality so he can know how to deceive you.
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These reasons keep me from converting my blog into a sort of a diary. I am restricting my blog only to theoritical discussions and technical opinions only. So you might feel that this blog is sort of “dry”.
No blogger can ever know who is reading his blog. It might be your future boss or your future friend. And this is actually happened. I was reading someone's blog. And after 2 days, I've met him as a total conincedence. I didn't show him that I know him, it will be a strange situation —especially that he doesn't know me—, although I actually knew about him what can fill 2 pages. I knew his birthdate, his favorite topics and his friends. He was really a sincer blogger, he almost wrote his life day-by-day in his blog. Funny it was like I lived each day with him like a close friend just by reading his blog. I don't like this type of blogging.
Although blogging comes from “web log”, but i don't see why not specialize blogging as each blogger wants about his blog. Of course this does not mean that I convert a blog into a forum for example!
I don't think that you will reach this line. You will get bored and leave before completing. Anyway this is my blog and I write however lengthy posts as I like. It is up to you to read a whole post or not, but please do not comment on a post you didn't read it all.
I blog only when I have nothing else to do. So you will always find the posts lengthy. Presumably, it is not because I like torturing the reader. But because I like to write my whole point of view as a block.