Greenhouse gases are gases in the Earth's atmosphere that trap heat and contribute to the greenhouse effect, leading to global warming. The primary greenhouse gases include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases. Human activities, such as burning fossil fuels, deforestation, and industrial processes, are major contributors to the increasing levels of greenhouse gases in the atmosphere. Research in this area focuses on understanding the sources and impacts of greenhouse gases, developing strategies to mitigate their emissions, and finding solutions to address climate change.