Cores segment the workload, SIMD batches segments of repetitive calculation, and superscalar picks apart independent individual instructions

Cores: must be utilized manually by software developers (workloads never automatically divided across cores) and run totally independent pieces of code (independent as in unique programs or pieces of execution).

SIMD: used to vectorize workloads within the same workload (same program) but still requires knowledge of the programmer (because not all code practices can be automatically vectorized).

Superscalar: sets of instructions that have been identified as independent of each other at the hardware level so that they can be run in parallel. Cannot be manually controlled by programmers.