Citation analysis involves using quantitative data derived from the use of citations (bibliographies, works cited, or reference pages in books, articles, or other publications) to analyze the scholarly impact of a researcher, a group of researchers, or a publication. Citation analysis can be as simple as counting the number of times a person or group has been cited by others, a ratio of their citations to their output, or some other mathematical function that relates their citation counts to other measures.
Web of Science is a citation index, which means that the records in the database contain information on citations made in that publication, and it links that information so you can identify which publications have cited that one and how many times a publication has been cited.
Bibliometrics is concerned with the analysis of research based on these citation counts and patterns, allowing for the identification of trends in research patterns and a quantitative evaluation of research outputs. Web of Science can therefore be used to identify many of these metrics. You can use the Analyze Results feature in Web of Science to identify citation metrics and trends relating to authors, publications, institutions, and collaborations. For more in-depth analysis, you may wish to use other resources available through the InCites platform.
Google Scholar covers articles, theses, books, abstracts, and other scholarly literature from all broad areas of research and may include preprints and web-published reports as well as published literature. Since Google Scholar indexes information from multiple sources (provided by publishers, included in databases such as PubMed, found on the public web, etc.), there is no comprehensive list of what publications it covers. However, for many fields, the greater number of publication formats included means that Google Scholar may find citations that were not discovered in Web of Science.