Why do we share so much about ourselves online?

My mom recently (earlier tonight) asked if I had Google’d myself recently. Being the tech-geek I am, I had done so within the last few weeks. She was amazed to find all of my “away messages” and “personal” information at the top of the search results. She questioned me about why I shared so much and she didn’t think it was a good idea. I tried to briefly explain but it just didn’t make sense to her. I realized that I’m growing up/living in a much different time than my parents and older generations did.

While I think nothing of posting what I ate for dinner or a picture from my weekend, many people find this an invasion of their privacy. But this is definitely not an invasion of privacy: I’m posting it all myself! Then the question is, why?

There are a few reasons why I personally share “so much personal” information. First of all, the Google results help prove my point. On the first page, 7 of the 10 results are links to content that I personally generated: my blog & photoblog, a tweet, a Digg, my LinkedIn profile, and my Cork’d profile. I think this is critical, because rather than having information posted by somebody else (possibly someone I don’t know who has posted false or inaccurate data) I have complete control over this content. If I don’t want someone to know what I’m doing tomorrow, I don’t post that information. On the other hand, if I found a really great website that I think would be useful to others, I simply digg it and everyone knows I enjoyed that site. This is especially helpful if the person knows (of) me because a recommendation from a trusted friend is almost always better than from a stranger.

This brings me to my second reason for posting online: I like to share my life with all of my friends. Along with the Web2.0 ability for everyday people to post content, many of today’s services link together. For instance, when I post to Twitter, I could have it set my “status” on Facebook and Plaxo and also show up on my blog. When I post a picture to Flickr, it shows up as a tweet, on my Mini-Feed on Facebook, and on my Pulse on Plaxo. By linking my various accounts together, I can share all parts of my online and personal life that I choose to with all of my friends (most of whom use Facebook, with only a few on Twitter, Flickr, or Plaxo). Since I don’t get to physically see many of my college or work friends very often, this is a way to keep them all informed of what I am doing all the time. I still use direct contact with many of them, but obviously I can’t do that with everyone all the time.

What other reasons do you have for sharing, or not sharing, personal information on the web? Do you use services besides the ones I listed…tell me about them! Share with me in the comments….