Temporal Locality ✔✔data location is referenced when it will tend to be referenced again soon Spatial Locality ✔✔data location is referenced, data locations with nearby addresses will tend to be referenced soon Block (or line) ✔✔the minimum unit of information that can be either present or not present in a cache Miss Penalty ✔✔the time required to fetch a block into a level of memory hierarchy form the lower level includes: time to access block, transmit for one level to another, insert it into the level that experienced the miss, and pass block back to requestor Hit Time ✔✔time required to access a level of memory hierarchy includes: time needed to determine whether hit or miss Flash Memory ✔✔memory type with EEPROM (electrically erasable programmable read-only memory) Track ✔✔one of thousands of concentric circles that make up the surface a a magnetic disk Sector ✔✔one the segments that make up a track on a magnetic disk the smallest amount of information that is read or written