A dual inline memory module (DIMM) consists of a number of memory components (usually black) that are attached to a printed circuit board (usually green). The gold pins on the bottom of the DIMM provide a connection between the module and a socket on a larger printed circuit board. The pins on the front and back of a DIMM are not connected to each other.
184-pin DIMMs are used to provide DDR SDRAM memory for desktop computers. Standard 184-pin DIMMs are available in PC1600 DDR SDRAM, PC2100 DDR SDRAM, PC2700 DDR SDRAM, and PC3200 DDR SDRAM.