Editor

A text editor is a program for editing plain text files, such as source code for programs and scripts.

Editors for Unix

emacs, nano, pico, vi / vim, ...

Editors for Windows

"Notepad" comes with a standard installation of MS-Windows.

Better yet are "programmers editors", such as akelpad, emacs, geany, notepad++ vim, ...

They provide many additional features, like syntax-highlightning paren-matching, extensions, and more.

See also Free text editors