Facebook has been with us for seven years. It has gone from zero to 500 million customers in that time. What began as a social tool for college students has become ubiquitous. Baby Boomers use it. Our grandparents use it. It is even the "star" of an Oscar-nominated movie, "The Social Network."

Somewhere along that path, Facebook had a profound impact on entertainment, commerce, advertising and my own field, politics.

Like other communications tools before it--television, radio, the printing press--Facebook is changing politics. It is doing that by lowering the costs of communicating and forcing politicians to directly talk to people.

Right before our eyes we see Facebook's effects. In Egypt, protesters used Facebook to organize rallies. At one point last month, Facebook accounted for 42 percent of Egyptian web traffic.

In the United States, Sarah Palin does not post her views on a personally-branded website. Instead, she posts them on Facebook where they become fodder for political reporters, talk radio hosts, and bloggers.

Then candidate Barack Obama grew a huge community on Facebook and took it to another level by building My.BarackObama.com where supporters could share news, hold house parties, fundraise, organize rallies, and connect as an online community.

Yet Facebook and other social media are not revolutionary political technologies. Since the beginning, humans have shared information with their friends, family, and neighbors. Meetings have been organized and political organizations have been built before Facebook and the Internet existed. But what Facebook has done is 1) make it easier to communicate; 2) extend the sphere of who your friends and acquaintances are; and 3) let politics become more personally-meaningful.

If someone finds a video, a news story, an issue, or a candidate they deeply care about they can go beyond just talking to their friends and family on the phone or in person. Now, they can post something on Facebook and have a conversation. Those friends can then share with their friends amplifying the reach of every Facebook user.

Facebook's vast network expands a citizen's reach beyond geography. Your friends are more than who you know in your neighborhood or town. Facebook helps connect people with similar passions. A Sarah Palin fan in Oklahoma can talk with a fan from New York. A Barack Obama fan in Wisconsin can share a campaign video with someone in Florida who they have not met in person but know because they met through the President's Facebook page.

Also, Facebook allows people to put a human face and a personal touch on politics. A candidate may have a message about creating jobs that is blasted out through advertising, but a passionate supporter can frame that message into a personal story that fits their circle of friends. This is old fashioned one-to-one politics supercharged by the Internet.

What tools like Facebook have done is force politicians and political communicators to up their game and create compelling, meaningful content that will touch people so much that they want to share it with others. In addition, politicians are now forced to engage with the public instead of talking at them. It's a slow process but we're seeing that kind of fruitful engagement beginning to be used by Congressmen and Senators.

In short, Facebook has caused politics to rely more on personal connections, easier communications, and the need to create meaningful content. All that has happen in the last seven years. Imagine how politics will change in the next seven years.

Sean Hackbarth is a Senior Campaign Manager for CRAFT | Media / Digital. He has worked on online communications for Sen. Lamar Alexander and Fred Thompson. Follow him on Facebook and Twitter.