This usually means that data is organized in ways that are friendly to cpu cache, instruction parallelism, and multithreading. Lining up data in arrays, arrays

This usually means that data is organized in ways that are friendly to cpu cache, instruction parallelism, and multithreading. Lining up data in arrays, arrays of positions instead of arrays of objects each of which has a position, and so on. Usually this is done via an entity component system.