SO-DIMM

An SO-DIMM, SODIMM, or small outline dual in-line memory module, is a type of computer memory built using integrated circuits.

SO-DIMMs are a smaller alternative to a DIMM, being roughly half the size of regular DIMMs. SO-DIMMs are often used in systems that have limited space, such as notebooks, small-footprint personal computers (such as those with a Mini-ITX motherboard), high-end upgradable office printers, and networking hardware like routers and NAS devices.