Google Scholar is a search engine which provides a simple way to broadly search for research literature.
Using the search feature, you are able to discover a wide variety of online scholarly literature, including: journal articles, theses, preprints, technical reports, conference proceedings and books. Google Scholar explores the bibliographic information of sources as well as the text to provide you with optimized search results.
Currently, Google Scholar allows you to search and read published opinions of US state appellate and supreme court cases since 1950, US federal district, appellate, tax and bankruptcy courts since 1923 and US Supreme Court cases since 1791. In addition, it includes citations for cases cited by indexed opinions or journal articles which allows you to find influential cases (usually older or international) which are not yet online or publicly available.
It is important to note that Google Scholar's coverage is is wide-ranging but not comprehensive. It can be a research source, but should not be the only source you use.
To use fully take advantage of Google Scholar, a Google account is required. If you already have a Gmail address, you already have a Google account. Note that you do not need to use Gmail to have a Google account.
the above information is taken from https://support.google.com/accounts/answer/27441?hl=en
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