Web of Science is an online subscription-based scientific Citation indexing service and provides most reliable, integrated, multidisciplinary research.It's now maintained by Clarivate Analytics.Web of Science previously known as Web of Knowledge.
The Science Citation Index Expanded SCIE is the larger version SCI. The indexing database covers more than 9,200 notable and significant journals, across 178 disciplines, from 1900 to the present. These are alternatively described as the world's leading journals of science and technology, because of a rigorous selection process.
The Social Sciences Citation Index SSCI is a commercial citation index product of Clarivate Analytics. It was originally developed by the Institute for Scientific Information from the Science Citation Index.
The Arts & Humanities Citation Index AHCI , also known as Arts & Humanities Search, is a citation index, with abstracting and indexing for more than 1,700 arts and humanities journals.Subjects covered are the Arts, Humanities, Language (including Linguistics), Poetry, Music, Classical works, History, Oriental Studies, Philosophy, Archaeology, Architecture, Religion, Television, Theater, and Radio.
The Emerging Sources Citation Index ESCI was launched in late 2015 by Thomson Reuters as a new database in Web of Science.This index was produced by Clarivate Analytics since 2017, which includes over 3,000 journals from various areas of research.The journal’s index in this ESCI will not come with an impact factor(IF).