Altmetrics, or alternative metrics, refer to non-traditional bibliometrics compared to more traditional citation impact metrics like impact factors and SJR numbers. The term was proposed in 2010 and initially referred to article level metrics. It was later appropriated by a company to sell services about altmertics to scholars.
Altmetrics can also be applied to people, journals, books presentations, videos, web pages, etc. Altmetrics did not initially refer to citation counts but reflected scholarly impact based on social media coverage, online news media, and other non-scholarly venues. Generally altmetrics are considered to be a complement to traditional metrics. Projects such as Our Research (formerly called ImpactStory) and various commercial services have grown up around the concept (Altmetric and Plum Analytics, and Mendeley, for example).
Almetrics may include data about:
These measures are not given as much credence as traditional metrics because a work could be viewed, downloaded and mentioned online but not used or cited in the scholarly literature and therefore may not have the weight of traditional metrics in the promotion/tenure process. Altmetrics generally offers insight about the potential impact of a paper rather than the actual impact.