2D NAND is a type of flash memory technology used in storage devices like solid-state drives (SSDs) and USB flash drives. It consists of memory cells arranged in a two-dimensional layout, allowing for efficient data storage and retrieval. Each cell can hold multiple bits of data, which enhances storage capacity while maintaining a compact size. The design of 2D NAND enables faster read and write speeds compared to traditional hard drives. However, as technology advances, newer types like 3D NAND are becoming more popular, stacking memory cells vertically to increase density and performance even further.