We investigate and characterize the effect of compressibility and rarefaction on vortex structures in the benchmark lid-driven cavity flow. Direct numerical simulations are performed. employing the unified gas kinetic scheme to examine the changes in vortex generation mechanisms and the resulting flow structures at different Mach and Knudsen numbers. At high degrees of rarefaction. https://www.roneverhart.com/Asus-ROG-Zephyrus-GU502LV-BI7N8-15-6-4K-3840x2160-IPS-Intel-i7-10750H-2-6-GHz-16GB-1TB-SSD-NVIDIA-GeForce-RTX-2060-6G/