Squidoo is a website designed to make it easy for anyone, for free, to set up a single page on a topic he or she knows or cares a lot about. Advertising revenue is shared with these content creators, and some of it is given to charity. Squidoo was launched in October 2005 by Squidoo.com, LLC based in Irvington, New York; the site came out of beta testing in March 2006.

Squidoo is a network of user-generated lenses --single pages that highlight one person's point of view, recommendations, or expertise. Lenses can be about anything, such as ideas, people or places, hobbies and sports, pets or products, philosophy, and politics. Lenses aren't primarily intended to hold content; more emphasis is placed on recommending and then pointing to content on the web. Annotation and organization and personalization delivers context and meaning.

Users who create lenses are called lensmasters. A lensmaster uses the tools available online to provide links, feeds, abstracts, and lists to users who are trying to make sense of a topic. For example, a single lens could point to Flickr photos, Google maps, blogs, eBay auctions, YouTube videos, and other links. Lensmasters are encouraged to promote personal agendas, expertise, causes, products, and opinions.

Squidoo splits its revenue with its "co-op" of lensmasters. 5% goes straight to charity, first. Then 50% goes to the lensmasters. 45% goes to Squidoo. The site is estimating that nearly half of all the lensmasters on the site are donating their royalties to any of 65 featured charities, ranging from NPR and the American Heart Association to smaller organizations like Chimp Haven and Planet Gumbo.

Squidoo was founded by author, speaker, and notable blogger Seth Godin. On Godin's founding team was his book editor Megan Casey, former Fast Company employee Heath Row, Corey Brown, and Gil Hildebrand, Jr.

In medical terminology, addiction is a state in which the body relies on a substance for normal functioning and develops physical dependence. When this substance is suddenly removed, it will cause withdrawal, a characteristic set of signs and symptoms. Addiction is generally associated with increased drug tolerance. In medical terms, addiction is not necessarily associated with substance abuse since addiction can result from using medicine as prescribed by a doctor.

However, common usuage of the term addiction has spread to include a wider range of meanings, including ones associated with psychological dependence. It is used to describe a recurring compulsion by an individual to engage in some specific activity, despite harmful consequences to the individual's health, mental state or social life. The term is often reserved for substance abuse problems or drug addictions but it is sometimes applied to other compulsions, such as problem gambling, and computer addiction. Factors that have been suggested as causes of addiction include genetic, biological/pharmacological, spiritual and social factors.