This document discusses global climate change and its various aspects. It provides an overview of the history and science of global warming, summarizing that increasing greenhouse gas emissions are causing the planet to warm due to human activities. Main greenhouse gases like carbon dioxide, methane, and nitrous oxide are explained in terms of their sources and impacts. The effects of global warming are expected to include continued temperature rise, more extreme weather, sea level rise, and effects on ecosystems. International agreements to address climate change like the UNFCCC and Kyoto Protocol are also summarized.