Companies are increasingly crunching "big data" culled from your Web search history, email traffic and social networking sites to micro-target you with advertisements that fit your age, gender and even shopping preferences.
But companies aren't the only ones getting personal online. Political campaigns also are learning as much as they can about you to tailor their appeals for votes and cash.
Joseph Turow, author of "The Daily You: How the New Advertising Industry is Defining Your Identity and Your Worth," gave a great rundown of these tactics in a February interview on NPR's Fresh Air.
The Republican presidential hopefuls are in the micro-targeting game too but are less likely to share their data with other campaigns or organizations, according to their privacy policies, he said.
For a fascinating look at how personal data can help a campaign hone its message, check out this Tuesday post from ProPublica detailing how the Obama campaign tailored a fundraising appeal based on the age, gender and donation history of the recipients.