What does CL mean?

[cezartrancanau]

Hello. Recently I have been thinking of buying a new pc. What does CL mean between:
2666MHz CL16 vs 2666MHz CL19
Is CL19 much better? If yes, is that a lot of difference? Does it matter?
Thanks.

 

[punkncat]

Are we talking about RAM timings?

Can you provide a link to said format so we see it in perspective?

 

[rgd1101]

http://www.crucial.com/usa/en/memory-performance-speed-latency

 

[bignastyid]

Clock Latency also know as CAS(Column Access Strobe) latency. With CL the lower the number the better when the clock speed is the same.

 

[punkncat]

^that one