Notepad-- is a cross-platform Qt/C++ desktop text editor with a Notepad++-style feature set. The production application is a monolithic Qt Widgets GUI that provides multi-tab editing, syntax highlighting for dozens of languages via vendored Scintilla/QScintilla, hex editing, file and directory comparison, encoding detection and batch conversion, find/replace across files, batch rename, macro recording, user-defined languages, theming, and an optional plugin system. The main entry point is src/main.cpp, which handles argument parsing, single-instance IPC, and session restore, then launches the central CCNotePad main window in src/cceditor/ccnotepad.cpp. Core editing behavior is implemented through ScintillaEditView and QsciDisplayWindow, while settings are persisted through QSettings and the NddSetting helper.