For some topics, patents may provide some useful information. Although the most likely reason to search the patent literature is to identify specific technological advances and inventions, other reasons include noting trends in an area, and identifying areas of interest of particular companies.
Search the full-text of United States patents from 1976 to current at the USPTO's official site. Images of patents from 1790 to current are also available at this site, searchable by Patent Number or by the current Class/ Subclass.
Find information on patents from Europe, Japan, WIPO (World Intellectual Property Organization), and the United States. Options include searching in the original language of the patent, or searching using English abstracts.