This document discusses the characteristics of cracks in tight sandstone reservoirs. It finds that the main types of cracks are tectonic cracks, bedding cracks, and diagenetic cracks. Tectonic cracks are irregular and oblique, bedding cracks form between layers of different lithology, and diagenetic cracks are micro-cracks controlled by diagenetic processes. The development of cracks is controlled by tectonic stress, sedimentation, and diagenesis. Cracks improve the physical properties of tight reservoirs by providing pathways for fluid flow and sites for secondary porosity development through dissolution.