RAM, or Random Access Memory, is a type of computer memory that temporarily stores data and programs that a computer is currently using. It allows for quick access to information, enabling smooth operation and multitasking. The more RAM a computer has, the more applications it can run simultaneously without slowing down. When a computer is turned off, the data in RAM is lost, as it is volatile memory. This is different from hard drives or solid-state drives, which store data permanently. Upgrading RAM can improve a computer's performance, especially for tasks like gaming, video editing, or running multiple applications at once.