As businesses offer e-marketing and online shopping, customers can get market information from their computers or cell phones and buy goods or find services without leaving home twenty-four hours a day and seven days a week (24/7). They can read ads on the Web or from e-mail, get e-coupons, view pictures of goods, compare prices, and make purchases with a few clicks of their mouse, saving the time and money it would take to shop in person at a brick-and-mortar store. At the same time, ebusinesses can reduce costs in distribution channels and physical store space and thus pass the savings on to customers.
If you sign up for something and the terms include words like "Sign up to receive updates from us and our partners that we think you'll like," your email address is likely being collected for a shared or sold list. A subset of this method is called co-registration. This is where you sign up at a website, but that website also automatically, or nearly automatically, signs you up for other sites. They try to legitimize this by informing you of the additional subscriptions, or providing boxes to uncheck. This is a situation where it's not the subscriber’s intention to sign up for the material they will be receiving.
Consumers also face malware risks, i.e. malvertising, when interacting with online advertising. Cisco's 2013 Annual Security Report revealed that clicking on ads was 182 times more likely to install a virus on a user's computer than surfing the Internet for porn. For example, in August 2014 Yahoo's advertising network reportedly saw cases of infection of a variant of Cryptolocker ransomware.
Publishers can offer advertisers the ability to reach customizable and narrow market segments for targeted advertising. Online advertising may use geo-targeting to display relevant advertisements to the user's geography. Advertisers can customize each individual ad to a particular user based on the user's previous preferences. Advertisers can also track whether a visitor has already seen a particular ad in order to reduce unwanted repetitious exposures and provide adequate time gaps between exposures.