Stands for "Random Access Memory" and is pronounced "ram." RAM is a common hardware component found in electronic devices, including desktop computers, laptops, tablets, and smartphones.
The amount of RAM in a device determines how much memory the operating system and open applications can use. When a device has sufficient RAM, several programs can run simultaneously without any slowdown. When a device uses close to 100% of the available RAM, memory must be swapped between applications, which may cause a noticeable slowdown.
Therefore, adding RAM or buying a device with more RAM is one of the best ways to improve performance.