The Internet has emerged as a major source of information in the United States. About 70 % of the American population is online [1], and almost 80% of online users have looked for health information at one time or other, on a variety of topics, including diet, fitness, drugs, hospitals, new treatments, alternative medicines, and doctors [2].

The number of web sites on health runs into the tens of millions. For example, a casual search for "cancer" yields about 274 million hits. However, despite the increasing penetration of the web and the amount of health information online, there are significant factors that influence its widespread adoption as a source of health information [3].

1. There exists a "digital divide," with people from higher income and education groups demonstrating greater access to and usage of the Internet as compared to those who are from lower SES groups [3].
   
2. Even if access is improved, few web sites offer health information that is designed to cater to the needs of those in the lower SES groups (who are more likely to have lower literacy skills). For example, a recent analysis reported a mismatch between the increasing number of low-literacy users and the number of web sites on colorectal cancer that could meet their needs [4].
   
3. Use of online resources for health information is influenced by broadband access and experience in usage. For instance, a recent study showed that broadband users are twice as likely as home dial-up users to do health research online [5]. Those who have less education, lower income, and who are older are less likely to have broadband connections at home [6].

In spite of the long-standing evidence of inequality in access, some researchers are now suggesting that these differences will disappear with further technological advances [7]. This is a reasonable speculation, given the saturation level diffusion of such technologies as electricity and the telephone and the deepening penetration of cell phone.