The primary difference between renewable and non-renewable resources lies in their availability and sustainability. Renewable resources, such as solar, wind, and hydro energy, can be replenished naturally over short periods and are sustainable in the long term. In contrast, non-renewable resources, including fossil fuels (coal, oil, natural gas) and minerals, exist in finite amounts and take millions of years to form. Once depleted, non-renewable resources cannot be replaced within a human timescale, making their sustainable management critical for future energy and resource security.