CotEditor was specifically designed for macOS. It behaves and looks exactly like macOS applications should. CotEditor launches quickly so you can start writing your text as soon as you want. CotEditor is an open-source project, which allows anyone to contribute. You can colorize more than 50 languages, including HTML, PHP and Python. You can also make your own settings. Split a window into multiple windows to view different parts of your document simultaneously. Display Unicode character data for each character in your document in a popover. There are no complicated configuration files that require geeky knowledge. All your settings, including syntax definitions or themes, can be accessed from a standard preferences window. You don't have to lose any of your saved data. CotEditor automatically backs up your documents while you edit. You can check and list-up any characters that are not compatible with the desired encoding.