This chapter provides a brief overview of the dynamics and pattern of climate variability from the Plio-Pleistocene to the modern day including Quaternary ice ages, millennial scale variability, abrupt climate change, and the Holocene. Selected examples of terrestrial, marine, and cryospheric archives of paleoclimate information and the proxy climate information that can be quantitatively extracted from them are presented. Although the primary focus of the chapter is climate variability itself, a few examples of the past interactions between climate and human societies are also presented. The chapter concludes with some speculative comments on lessons that can be drawn from such studies of the past with relevance to modern day concerns.