The document discusses various metrics used to evaluate journals and authors, including the Impact Factor, h-index, and Eigenfactor. It describes what each metric measures, how it is calculated, and its advantages and limitations. In particular, it notes that the Impact Factor only looks at citations over a two year period, while the Eigenfactor and SJR take a longer, five year view and weight citations differently based on the influence of the citing journal. For authors, the h-index and its variants aim to capture both productivity and citation impact, but have limitations such as field differences and inability to decrease over time.