SIMM

A SIMM is an older type of memory module used for RAM in personal computers. SIMM stands for Single In-line Memory Module, and it differs from a DIMM (the most predominant form of memory module today) in that it may be only installed in pairs on a motherboard. The first variant of SIMMs had 30 pins, and the later variant had 72.

To install a SIMM, the module must be placed in the socket at an angle, and then rotated into position. To remove one, the two metal clips at each end must be pulled to the side, and then the chip must be tilted back and pulled out.

Different SIMM types are EDO and FPM.