Greenhouse gases (GHGs) are gases that trap heat in the Earth's atmosphere, leading to the warming of the planet. The most important greenhouse gas is water vapor, however, certain human activities can also lead to the release of other gases that trap heat, these are commonly known as anthropogenic greenhouse gases. The most significant anthropogenic greenhouse gases are: Carbon dioxide (CO2): This is the most important greenhouse gas, and is primarily released through the burning of fossil fuels (such as coal, oil, and natural gas) for energy and transportation. Methane (CH4): This is a potent greenhouse gas that is released through activities such as the production of natural gas and oil, and the raising of livestock. Nitrous oxide (N2O): This gas is released through activities such as the use of nitrogen-based fertilizers in agriculture and the burning of fossil fuels. Fluorinated gases (F-gases): These are a group of synthetic gases that are primarily used in refrigeration and air conditioning systems, and in the manufacturing of certain products. They include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs). Each greenhouse gas has a different global warming potential (GWP) and stays in the atmosphere for different period of time. CO2 stays in the atmosphere for hundreds of years while CH4 stays for around 12 years, but CH4 is 28 times more potent than CO2 over a 100 year period.