Beginners question on Timings

[Notorious Lee]

Sorry for this basic question but when choosing RAM it states the timings what do these figures mean?

Thanks & again sorry for such a simple question but i'm still learning.

 

[Defcon5]

DDR or DDR2?

 

[Jimmy1983]

DDR or DDR2?

Yeah iam slightly new to understanding timings for DDR2. If someone could explain them to me please