big.LITTLE
ARM's architecture that combines large, powerful cores ("big") with small, energy-efficient cores ("LITTLE") on the same chip. Light tasks run on the frugal cores, heavy ones on the strong cores — so you get both long battery life and high peak performance.
Idea: a single core type is a compromise — either fast-but-thirsty or frugal-but-slow. big.LITTLE (ARM, 2011) gives both: large out-of-order cores for demanding burst work (open an app, render a page) and small in-order cores for background tasks and idle (sync mail, play music) that draw a fraction of the power. The scheduler moves threads between the core types as needed. It became standard in practically all smartphone chips (a key to modern mobile battery life) and then spread to desktop/laptop: Intel's P-cores/E-cores (Alder Lake+) and Apple's M-series use the same heterogeneous principle. Later ARM variants (DynamIQ) mix more core types more freely. The base model for heterogeneous cores. Related to heterogeneous cores and P-core/E-core.