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Why is DRAM commonly used as a computer's main memory?

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Dynamic random access memory (DRAM) is the standard choice for a computer's main memory primarily due to its high density and cost-effectiveness compared to static random access memory (SRAM).12

Because a DRAM storage cell uses fewer electrical components—specifically a single transistor and a capacitor—it is physically much smaller than an SRAM cell, which requires four to six transistors to form a flip-flop. Consequently, a DRAM chip of the same physical size can hold several times as much data as an SRAM chip.123

While SRAM is significantly faster, it is also more expensive and less space-efficient, which limits its use to small amounts of high-speed cache memory and CPU registers. DRAM, despite requiring periodic refreshing because its capacitors gradually leak charge, provides the necessary capacity and affordability to serve as the primary working area for active applications and data.2431