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SIMM, which stands for Single In-line Memory Module, is a type of computer memory module consisting of a small circuit board holding RAM chips that plugs into a motherboard. It was a predecessor to modern memory modules and was designed to make it easier to install and upgrade a computer's memory compared to individual chips.

Key features and function

Purpose: A SIMM's primary function is to increase a computer's random access memory (RAM), which allows the computer to multitask and run applications more quickly.

Construction: It is a small, rectangular circuit board with a single row of contact pins along one edge.

Installation: SIMMs plug into a dedicated slot on the motherboard.

Evolution: Early SIMMs had 30 pins and an 8-bit data bus, while later 72-pin versions used a 32-bit bus.

Obsolescence: Because modern computers use a 64-bit bus, SIMMs must be installed in pairs to function correctly. They have largely been replaced by the faster and more efficient Dual In-line Memory Module (DIMM).