Notcurses is a C library for building rich terminal user interfaces (TUIs) with full pixel graphics, multimedia support, and a widget toolkit. It provides both a full-screen rendered mode and a direct mode for simple output. The library abstracts terminal capabilities (terminfo, escape sequences, pixel protocols like Sixel and Kitty) and offers a composable plane system with z-ordering, transparency, scrolling, and damage-based rendering. It includes built-in widgets such as reels, selectors, menus, progress bars, plots, trees, and tabbed containers, as well as a multimedia backend (FFmpeg/OpenImageIO) for image/video decoding and streaming. The architecture is centered around a core C library with official C++ and Python bindings, plus command-line tools (ncplayer, nctetris, notcurses-demo, notcurses-info, etc.) that demonstrate its capabilities. Input handling uses an automaton-based parser for escape sequences and mouse protocols. The codebase is substantial and well-tested, though some areas show incomplete features and platform-specific complexity.