Google Knol is a free online collaborative knowledge database or an experts' wiki but not an encyclopedia. Knol is not a direct competitor of Wikipedia, at least not in its current version. Wikipedia is anonymous -- there is no single editor in charge. In contrast, Knol includes the author name in the URL of the article. Google expects multiple knols on one subject rather than the current Wikipedia model of one article on a subject.
There is a definite focus on medical topics -- most of the 300 or so starting "knols" are disease-based and authored by doctors. Will Google Knol be the mythical universal textbook of medicine that Wikipedia never became (and was not meant to be)? UpToDate and eMedicine are close to that concept but UpToDate is prohibitively expensive and management-focused while eMedicine is limited in coverage.
An expert-written medical knol. Image source: Google Operating System, Creative Commons license.
Selected knols on allergy-related topics:
Nasal Polyps by Andrew Murr, UCSF
Seasonal Allergies by Paul Nadler, MD, UCSF
Asthma by John Fahy, UCSF
Chronic Obstructive Pulmonary Disease (COPD) by Stephen C. Lazarus, UCSF
Urticaria by Alan Rockoff
Read more in Google Knol Collaborative Knowledge Database = Universal Textbook of Medicine? at Clinical Cases and Images - Blog.
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