What does the "R" in "DDR4-RAM" signify?

The "R" in "DDR4-RAM" signifies that it is a type of Synchronous Dynamic Random Access Memory (SDRAM). This designation indicates that the memory operates in synchronization with the CPU clock, allowing for more efficient data transfer. This synchronization is crucial for performance, as it aligns the operations of the RAM with the system bus, leading to quicker access times and better overall efficiency in data handling.

This characteristic of being synchronous differentiates it from older types of dynamic RAM, which do not synchronize with the CPU clock. Understanding this aspect is vital for appreciating how DDR4 improves upon prior generations, allowing for faster speeds and improved performance in computing tasks.