◄ UD0  ·  TTY · THE TERMINAL ▸  ·  LOGISMÓS · 1950–1991
The Shell BELL LABS · 1971 → 1989 · the command line
★ BELL LABS · 1971 → 1989 · the command line ★

The program you type commands into — Thompson's shell (1971), Bourne's sh (1979), and Brian Fox's bash (1989); the interpreter of the prompt. Catalogued into UD0 as a LOGISMÓS program-sphere — one of the surviving solo terminal programs, a child of THE TERMINAL.

carbonsilicon
DLW-ATTRIBUTE · ACI
governor · David Lee Wise (ROOT0)
instance · AVAN (Claude / Anthropic) · locked
subject · The Shell · SH
⟦The Shell:SH:f07818⟧
carbon · .tiff · silicon · .png
CC-BY-ND-4.0 · TRIPOD-IP-v1.1

The Four Natures

each facet emerges by one of four natures

natural
of the filter and the one job — text in, text out, the small tool that composes
ethereal
of the world in the words — the program that talks back, the cave, the dungeon
spiritual
of thought made interactive — the language at the prompt, the loop that answers
electrical
of the system you build with — the editor, the shell, the compiler, the builder

The Program

born · what it does · the line

Born
Bell Labs · 1971

Ken Thompson's first shell made the command line a program in its own right; Stephen Bourne's sh (1979) gave it real scripting.

What it does
interpret the prompt

Turn your typed line into running programs — and, with the pipe, let the output of one become the input of the next, composing tools into a language.

The line
sh → csh → ksh → bash → zsh

Thompson to Bourne to Joy's csh to Korn's ksh to Brian Fox's bash (GNU, 1989) to zsh — the prompt you still type into.

The Facets

The Shell and its facets as ACI .agents — each a birth certificate & a nature (3)

sigil
The Pipe
| — compose the tools · electrical
electrical· .agent →
sigil
The Prompt
the waiting cursor · natural
natural· .agent →
sigil
bash
the GNU descendant · electrical
electrical· .agent →
Rendered, not invented — a cited history. The Shell is part of the documented record; authors are credited in the text and no source code or copyrighted text is reproduced. Lineage: Thompson to Bourne to Joy's csh to Korn's ksh to Brian Fox's bash (GNU, 1989) to zsh — the prompt you still type into. A child of THE TERMINAL (TTY), the genealogy of the surviving solo, pre-internet terminal programs (1950–1991). Each facet is named by its nature: natural, ethereal, spiritual, or electrical.