A SIMM is a type of computer memory module that contains a series of memory chips on a small circuit board and can be installed or upgraded by the user. SIMMs were widely used in personal computers during the 1980s and 1990s but have largely been superseded by DIMMs (Dual In-line Memory Modules), which offer higher capacity and faster performance.
SIMMs played an important role in early digital imaging and computer-based photography workflows, enabling increased memory for image processing, storage, and editing applications.