(CNN) -- People around the world began seeing messages from Facebook on Thursday encouraging them to start scrapbooking their life.
The service's new Timeline profiles, which Facebook introduced nearly three months ago at its annual conference, is now available to any of the site's 800 million users who decide to activate it. Soon, Facebook will turn it on for everybody with an alert at the top of profiles, the company said in a blog post.
Timeline will arrange a user's posts, photos and important milestones (weddings, births of children, etc.) chronologically in two columns of information, with a blue line marked by dates running vertically down the middle. On the right, visitors can easily skip to certain months or years to see what was happening at that time in a person's life, and below that is advertisements.
In addition to a standard profile picture, users can now set a cover photo, a large shot that appears at the top of each Timeline profile.
Facebook has said the idea behind Timeline is to chronicle someone's life and its major events over many years instead of the social network's current profile pages, which tend to emphasize the here and now.
For those anxious to see what kind of past info or photos Facebook may find, the clock starts ticking as soon as Timeline is turned on. Once that happens, a user has seven days to review the new layout and edit things before it goes public and can be viewed by friends. Each user can choose during that time to unveil their page before the seven days are up; regardless, Facebook will publish the page automatically after a week.
People can choose to "feature" major life events, such as engagements or injuries (which is now an optional type of status update), or hide more embarrassing ones. A new Activity Log page makes it easier to see everything and to find certain posts.
Facebook app developers began testing Timeline profiles in September, and the company has not made significant changes to it since then. This update has followed Facebook's "slow rollout" mantra for product launches.
"We're more than what we did just recently," Facebook CEO Mark Zuckerberg said during the announcement earlier this year. "We want to design a place that feels like your home."
Inevitably, when Facebook makes changes, some users complain about the new look of their pages. In this case, many users may not be fully aware of Facebook's latest redesign until it shows up on the site.
"Facebook is about to completely change the way its profile pages look as part of the website's biggest redesign so far, and only a fraction of the website's 800 million users seem to have the slightest clue," wrote Mashable founder Pete Cashmore in a September column for CNN.
"So yes, you will hate the new Facebook profile when it launches ... " he added. "Then, like me, you'll realize that Facebook has unleashed something so remarkable that you didn't even recognize it at first: A meaningful social network. And ... you'll wonder why life wasn't always this way, and how you got by without it."