Gravity Waves (GWs) significantly influence structure of the entire atmosphere and coupling between atmospheric layers. Research on gravity waves is crucial for deepening our understanding of atmospheric dynamics and for improving the accuracy of atmospheric models. While gravity waves are well-known in the fields of astronomy and physics, they also play a vital role in atmospheric science, particularly in the study of airflow, wave propagation, and climate variability. This review highlights the following key findings: ① Satellites are suitable for observing the middle and upper atmosphere; radar is most effective for detailed observations of vertical wave propagation; and reanalysis data are best suited for analyzing global GW characteristics; ② Compared with non-orographic gravity waves, orographic gravity waves generally have longer vertical wavelengths and can propagate to higher altitudes; ③ Orographic gravity waves are easier to trace due to their relatively fixed sources; and ④ Common parameterization schemes effectively simulate the drag effects of orographic gravity waves, while single-wave and global spectral techniques can predict the east-west momentum flux of non-orographic gravity waves. However, the complete generation and evolution processes of both types of GWs cannot yet be accurately simulated. There is still considerable room for improvement in the observation, identification, feature analysis, and parameterization of gravity waves. In the future, advancements in observational technology are expected to yield higher-quality data, enabling a clearer understanding of GW characteristics. Based on this, progress in parameterization methods and the application of artificial intelligence techniques is anticipated to enhance our understanding of the formation mechanisms of both orographic and non-orographic gravity waves, thereby improving the accuracy of weather and climate simulations.