Journal Impact Factor (JIF) is a measure reflecting the average number of citations to articles published in journals, books, patent document, thesis, project reports, news papers, conference/ seminar proceedings, documents published in internet, notes and any other approved documents. It is measure the relative importance of a journal within its field, with journals of higher journal impact factors deemed to be more important than those with lower ones. Journal Impact factors are calculated in yearly/half- yearly/ Quarterly/Monthly for those journals that are indexed in Journal Reference Reports (JRR).

The Global Institute for Scientific Information (GISI) was founded by renowned scientist in 1990. A group of 40 scientist from various countries in different disciplines are started GISI with specific objective of providing quality information to the researcher.

GISI offering academic database services to researcher. Its mainly: citation indexing, analysis, and maintains citation databases covering thousands of academic journals, books, proceedings and any approved documents. All of these are available via GISI's Web of Journal Knowledge database service. This database allows a researcher to identify which articles have been cited most frequently, who has cited them and find out the Journal Impact Factor (JIF).

GISI also publishes the annual Journal Reference Report which list an journal impact factor for each of the journals that it tracks. Within the scientific community, journal impact factors play a large but controversial role in determining journal impact factor to a published research record.

A list of over 1000 journals is maintained by the GISI. The list includes engineering, management and science journals. Listing is based on published selection criteria and is an important indicator of journal quality and impact.