Terminal Color Picker

ANSI escape codes are byte sequences that terminals interpret as commands rather than printable characters. They start with ESC (ASCII 27, written as \033, \x1b, or \e) followed by [ and a parameter list. For colors: \033[31m sets foreground red, \033[0m resets all attributes. They're standardized by ECMA-48 and supported by virtually every Unix terminal emulator.

The 16 standard colors (codes 30–37, 90–97 for fg) are the oldest and most portable. 256-color mode (\033[38;5;Nm) adds a 6x6x6 color cube plus a 24-step grayscale ramp — supported by xterm, iTerm2, GNOME Terminal, and most modern terminals. Truecolor (\033[38;2;R;G;Bm) allows any 24-bit RGB value — supported by iTerm2, Kitty, Alacritty, Windows Terminal (v1.10+), and VS Code's integrated terminal.

Define color variables at the top: RED='\033[31m' and RESET='\033[0m', then use them with echo -e or printf. Example: echo -e "${RED}Error: file not found${RESET}". Use printf for portability: printf '%b' "${RED}Error${RESET}\n". The -e flag tells echo to interpret escape sequences — without it, the literal characters \033 are printed.

You can use raw escape codes: print('\033[32mSuccess\033[0m'). For real projects, use the colorama library (pip install colorama) which handles Windows compatibility: from colorama import Fore, Style; print(Fore.GREEN + 'Success' + Style.RESET_ALL). For 256 colors: print('\033[38;5;208mOrange text\033[0m').

Raw escape codes work: console.log('\x1b[32mSuccess\x1b[0m'). The chalk library is the standard choice: const chalk = require('chalk'); console.log(chalk.green('Success')). Chalk auto-detects color support, respects NO_COLOR env var, and has a clean chaining API: chalk.bold.red('Error'). For 256 colors: chalk.ansi256(208)('Orange').

The 16 standard colors have no fixed RGB values — each terminal theme defines its own palette. What is 'red' (code 31) in one theme might be a deep maroon in another. 256-color and truecolor values are more consistent because they specify exact RGB. For maximum consistency across environments, use truecolor (\033[38;2;R;G;Bm) when you know the terminal supports it, or stick to the 256-color palette.