Google uses your profile to provide public information about you to other Google users and anyone who searches for your name. Having a profile is optional, but it allows you to promote yourself and link to websites you want to showcase. Google is also increasingly linking Google Profiles to other services from Google and search features. If you write Web content, it's to your advantage to have a well-maintained profile.
Creating a Google Profile
To set up a profile, go to www.google.com/profiles. You may find that you already have a profile. If not, click on the Create my profile link to get started.
The first page is the About me tab. Everything you list in this tab is public. If you don't want your boss or your mother to see it, don't list it here. However, it may be to your advantage to use this page as a public resume or social networking calling card.
You can add information about where you live, list other websites, create a biography, and add a photo of yourself. The cities where you've lived will automatically be listed on a map.
At the bottom of the tab, you'll find an area marked Profile URL. This is the address of your public profile. The default address is www.google.com/profiles/your_user_name_here. If you are using a non-Gmail email address for your Google account, you can create a custom address. If you make something easy to remember, you can list your profile on business cards or easily link to it from other websites.
The Photos tab is also public. This lets you link your Flickr or Picasa Web Albums account to your profile and puts a strip of photos from your album underneath your name.
The Contact info tab is not public. You specify which of your contacts are able to see it. You can also set up groups of contacts, such as family members and coworkers. You either release all your contact information or none of it to the people you specify. As of this writing, there's no granular control over who sees which item, but Google is working on social networking services that will make contact sharing granular.
Once you've finished editing your profile, click Save changes. Your profile will start appearing in Google search results.
If you're using Google's +1 to mark websites and clippings as "+1" and share them, you'll have a +1 tab where all your +1 sites will be shared. This is by design, as a plus one marks a site as publicly noteworthy.