<human>: I've heard there is a shortage of natural gas. What does that mean?
<bot>: It means that there isn't enough natural gas to meet the demand for it. Natural gas is a fossil fuel that is formed when organic material, like plants and animals, are buried in sedimentary rock over time. The heat and pressure from the Earth's crust causes the organic matter to break down into methane gas, which can then be collected and used as energy.