> CLIs (that read input from stdin and spit out results to stdout/stderr) are useful in an automation/data processing pipeline. TUI's and GUI's can both be use

> CLIs (that read input from stdin and spit out results to stdout/stderr) are useful in an automation/data processing pipeline. TUI's and GUI's can both be used in the middle of a pipe when things require some manual fiddling, Git commit would be an example of this, opening vim to edit the commit message. Here's an example (https://stackoverflow.com/questions/8371877/ncurses-and-linux-pipeline/44884859#44884859 https://stackoverflow.com/questions/8371877/ncurses-and-linu...) of how you could create an ncurses TUI but still output to stdout. Dmenu (https://tools.suckless.org/dmenu/ https://tools.suckless.org/dmenu/) is a good example of a gui program that fits comfortably in a pipeline.