Publishing is an evaluative process in addition to being a method of scholarly communication. For this reason different tools, or "metrics" have been developed to gauge a published work's significance or to rate the success of a particular publication. Recently researcher profiles have also provided metric tools for authors. Traditional metrics are also known as bibliometrics. These employ quantitative analytics to assess the reception and impact of a publication and involve things like citation count, H-Index, or scholarly output numbers. Impact factors or impact ratings can also tell researchers about a particular journal's productivity and exposure. More recently a measurement tool known as Altmetrics has been developed to indicate the number of times an article has been shared or downloaded. In addition to providing a wider picture of a work's current impact, Altmetrics also gives a visual representation of available data and ratings rubrics.
A number of emerging metric tools are currently being used to quantify scholarly impact. The SCImago Journal and Country Rank tool allows users to see the difference in disciplinary and regional publications while Scopus and Web of Science have all developed their own tools to evaluate research. It is important to remember that researchers should not depend on one method or rubric to inform their decision about where to publish or which source to use. A better, more reflective way to gauge the quality of research is to integrate and analyze collective data points.
Within both traditional and current publishing models, a journal's Impact Factor (IF) is an important attribute to determine the relevance of a particular journal and its content. Impact factors measure the frequency with which the average article in a journal has been cited in a particular year. Databases such as Scopus often have "cited-by" or "highly cited" filters to determine an article's circulating capacity. This article from the Clarivate Analytics parent website contains some good information about the evolution of Impact Factors.