Memory modules are essential components in computers and other electronic devices, responsible for storing data temporarily while the device is in use. They allow the processor to access information quickly, which is crucial for smooth operation. Common types of memory modules include RAM (Random Access Memory), which is volatile and loses its data when powered off, and ROM (Read-Only Memory), which retains information even when the device is turned off. These modules come in various forms, such as DIMMs (Dual In-line Memory Modules) for desktops and SO-DIMMs (Small Outline DIMMs) for laptops. The capacity and speed of memory modules can significantly impact a device's performance, making them a key consideration when upgrading or building a computer system.