An Engadget explainer clarifies a basic but often confusing distinction in computer specifications: whether memory retains its contents when power is cut. Volatile memory, such as RAM, loses its data as soon as power is removed, while non-volatile memory, such as flash storage, keeps data intact afterwards. The article stresses that "volatility" only describes this power-dependent behaviour and says nothing about a memory type's speed, capacity or function, which is why devices combine several different memory technologies for different jobs.

The piece breaks down the main types on each side of the divide. On the volatile side, DRAM (including DDR5 and mobile LPDDR5X) serves as a computer's main working memory and needs constant refreshing to stop stored charge leaking away, while SRAM, used in processor caches like the 144MB found in AMD's Ryzen 9 9950X3D, is faster but reserved for small amounts of frequently accessed data. On the non-volatile side, NAND flash provides persistent storage in SSDs, tablets and USB drives, managed by a controller that handles error correction and wear levelling, while NOR flash is typically used to store firmware and code that devices can run directly without first loading it into RAM.