 The operational land imager, OLI, on Landsat 8 represents a generational change from heritage Landsat instruments in its design, while it maintains data continuity with the 40-plus-year Landsat data archive. It preserves the 30m ground sample distance, 185 km swath width and vis-slash-nir-slash-swir spectral bands. Furthermore, data continuity resulted from extensive pre-launch and on-orbit calibration and characterization campaigns. This paper presents an overview of the OLI design, the pre-launch characterization results and the on-orbit performance. This article was authored by Edward J. Knight and Geerk Feren.