Fossil records are the preserved remains or traces of ancient organisms found in sedimentary rocks. They provide crucial evidence about the history of life on Earth, showing how species have evolved over millions of years. Fossils can include bones, shells, footprints, and even imprints of leaves, helping scientists understand past environments and ecosystems. By studying fossil records, researchers can reconstruct the timeline of life, identifying when different species appeared and went extinct. This information is essential for understanding the process of evolution and the impact of environmental changes on biodiversity. Fossil records also help in dating geological layers, contributing to our knowledge of Earth's history.