Renewable energy refers to energy sources that are naturally replenished and can be used without depleting the Earth's resources. Common types include solar energy, derived from the sun; wind energy, generated by wind turbines; and hydropower, produced from flowing water. These sources are considered more sustainable compared to fossil fuels, as they produce little to no greenhouse gas emissions. The use of renewable energy is essential for reducing reliance on non-renewable resources and combating climate change. By harnessing these clean energy sources, countries can work towards a more sustainable future, improve energy security, and create jobs in the growing green economy.