fmt

The fmt command line tool is used for formatting text files in Unix-like operating systems. It is part of the GNU Core Utilities package. This tool allows users to reformat text files by adjusting line breaks and word wrapping. It can automatically format text to a specified number of characters per line or a specific line length. The fmt command applies various algorithms to achieve optimal text formatting, ensuring readability and consistency. It supports options like "-w" to specify a specific line width and "-s" to preserve single spacing. The default behavior of fmt is to rearrange lines and wrap the text to fill the specified line width. It can be used to format plain text files, email bodies, and source code. The fmt command can be combined with other command line tools like cat or echo to process text input from files or pipelines.