RAM memory is a type of temporary memory where both the data of the applications that are running and the data of the operating system with which you are working are stored.
It is said that it is a temporary memory since the operating system of the device can erase it depending on the needs it has at all times, in this memory the data and instructions that the system needs to access are stored very quickly unlike the internal memory which is where they are permanently stored (until the system or the user decides to erase).
Therefore, the amount of RAM memory is a method to know how fast and fluid a mobile phone, tablet or smart watch can work, although it is not the only variable since it depends on the rest of the components.
8 GB of RAM is an amount of memory that we can consider very high for today's needs, only available for gaming or high-end devices. They also include 8 GB of RAM memory for professional-grade tablets used for example for graphic design or photo and video editing.