Yahoo! Inc. and OMD, a media communications company, announced a joint study that found the internet's greatest impact on shopping is assisting consumers in the decision-making process, regardless of whether purchases are made online or at retail stores.

The study, "Long and Winding Road: The Route to the Cash Register," found two-thirds (62 percent) of consumers use a combination of online and offline sources to gather information before they buy.

"The internet is far more than just another point of purchase; its biggest impact lies within the awareness and consideration process," says Wenda Harris Millard, Yahoo's chief sales officer. "The widespread adoption of social technologies gives marketers an even greater opportunity to continuously engage consumers and make connections across traditional and new media advertising, helping to build brand mindshare and increase offline sales."

Consumers say the internet is the most trusted shopping information source (54 percent), followed by magazines (34 percent) and TV (23 percent), according to the study.

The study also found that communal shopping online helped consumers learn more about a product. Findings showed that 25 percent of people have posted reviews of products or services online, providing a service to other shoppers.