Principle of Locality is of two types
Spacial as well as temporal
L + $\Delta L$ : This is spacial locality, this means, if I access this block of RAM, what is the chance, that consecutive two to three blocks will also be accessed.
T + $\Delta T$ : This is temporal locality, this means, if I access this block of RAM, what are the odds that, I am again in future gonna refer to the same block again.
Source: NPTEL, IIT Guwahati, Advanced Computer Architecture, Dr. John Jose
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