Fossil fuels are natural fuels formed from the remains of living organisms that were buried and subjected to high heat and pressure over millions of years. The three main types of fossil fuels are coal, oil, and natural gas. They are considered non-renewable resources because they take millions of years to form and are being consumed much faster than they are being replenished.

Fossil fuels have been the primary source of energy for human civilization for centuries, powering everything from transportation and electricity generation to heating and industrial processes. However, their widespread use has led to environmental concerns, primarily due to the release of carbon dioxide and other greenhouse gases when burned, which contribute to climate change.

Efforts are being made to reduce reliance on fossil fuels and transition to cleaner, renewable energy sources such as solar, wind, and hydroelectric power. However, fossil fuels continue to play a significant role in the global energy mix, and finding ways to reduce their environmental impact remains a key challenge for the future.