Final answer:
USBs generally use a type of cache known as NAND flash memory, which is a type of non-volatile storage technology that allows for fast data access. Some USB drives may also use a small amount of RAM cache to improve write performance.
Step-by-step explanation:
USBs generally use a type of cache known as NAND flash memory. NAND flash memory is a type of non-volatile storage technology that allows data to be stored and retrieved quickly. It is commonly used in USB drives due to its speed and reliability.
NAND flash memory works by storing data in blocks, which are divided into pages. When data needs to be accessed, the memory controller reads the entire block into a cache, allowing for faster retrieval of the requested data.
Some USB drives also use a small amount of RAM cache known as write cache, which helps improve write performance by temporarily storing incoming data before it is written to the NAND flash memory.