From the article: > That program, which he described as a “shell” around the computer’s whirring innards, gave inspiration—and a name—to an entire class of sof

From the article: > That program, which he described as a “shell” around the computer’s whirring innards, gave inspiration—and a name—to an entire class of software tools, called command-line shells, that still lurk below the surface of modern operating systems.