Global warming refers to the long-term increase in Earth's average surface temperature due to human activities, such as burning fossil fuels and deforestation, which release greenhouse gases into the atmosphere. These gases trap heat, leading to a gradual rise in temperatures and causing changes in climate patterns worldwide. Global warming has resulted in melting ice caps, rising sea levels, more frequent extreme weather events, and disruptions to ecosystems and wildlife. It is a major environmental issue that requires urgent action to reduce greenhouse gas emissions and mitigate its impacts on the planet.