What is a Text Editor?
A text editor is a program/app/application for editing text files.
A text editor is not a word-processor. The files that word-processors produce (for example
.docx files) are not text files.
(Read about Computer Files first if you don't already understand them)
Word-processor files have specific file formats that allow them to store much more information than just the text of the document. This is why, if you make a file in Word and try to open it in Pages, the formatting looks wrong or is missing altogether. Because Word and Pages use different file-formats and support different features.
Text editors all use a "plain text" file format.
Some plain text files have the extension
Other file extensions that you will come across are
.html for HTML (web page) files,
.css for CSS (styling) files and
Get a Text Editor
To write programs we need a text editor. Which one should you use?
Your Operating System already has some text editors built into it, and you could use one of those, but if you're free to install your own software on the computer that you're using, it's best by far to install Visual Studio Code from Microsoft.