A modal editor is a text editor whose keyboard behavior changes depending on the working mode. A user switches between modes to perform different tasks efficiently.
Modal editors aim to minimize hand movements, provide versatile keyboard control, and have a steeper learning curve.
For example, Vim is a text editor where users switch between insert mode (for text entry) and other modes for navigation and editing. Another example is Emacs, which uses different modes for writing text, programming, etc.