Final answer:
The most common type of main memory in computers is Random Access Memory (RAM). Cache RAM, or simply cache, is a small amount of high-speed memory that stores frequently accessed data and instructions from main memory.
Step-by-step explanation:
The most common type of main memory in computers is Random Access Memory (RAM). RAM is used to store data that is currently being used by the computer. It is volatile, meaning that it loses its contents when the computer is turned off or restarted.
Cache RAM, or simply cache, is a small amount of high-speed memory that is located close to the CPU. Its purpose is to store frequently accessed data and instructions from main memory. By having this faster storage close to the CPU, the computer can quickly retrieve information, improving overall system performance.