The `ed` Line Editor in Linux

`ed` is a text editor in Unix and Unix-like operating systems known as a "line editor." It is designed for editing text files line by line. It is primarily used in environments where the entire file cannot be viewed at once, such as on old terminal systems with limited screen space. `ed` is powerful but simple, making it very useful for batch editing and scripting, although it is less popular today compared to advanced editors like Vim or Nano.