Impact Factor is a method to assess the quality of a specific journal. This is done by quantifying the average number of times articles from an individual journal, published in the past two years, are cited or referenced in other articles in the current year.
To locate a journal's impact factor use:
JCR provides other data to evaluate and compare scholarly journals. These include a journal's impact factor, journals with the highest impact and those used most frequently, how quickly an article within a journal is cited, as well as the age of cited references within a journal.
Only original research and review articles are counted. Editorials, letters, etc. are not included in the tabulation. Cited-only journals have no source data.
To read more about impact factors: