RAM timing cycle

 The cycle time of RAM memory, measured in nanoseconds, indicates the time required to access information on the RAM module. In simpler words, the shorter the RAM cycle time, the less time it takes to read or write information from the memory cells.

Another type of measurement that is common in RAMs is CAL numbers. These numbers indicate the number of time cycles passed on the processor clock, to read or write data to the RAM memory. For example, if your RAM has CL16, it means that it takes 16 time cycles on the memory clock to store information on the memory or to read from the memory and transfer it to the processor.

source:

https://blog.logilook.com/shopping-guide/complete-guide-buy-ram/

https://www.crucial.com/support/articles-faq-memory/what-are-memory-timings

https://www.gamersnexus.net/guides/3333-memory-timings-defined-cas-latency-trcd-trp-tras