What is TXT (Plain Text)?

How Plain Text Works

TXT is the simplest possible document format: a plain text file is just a sequence of character codes, with no header, no metadata, and no markup. There is no bold, no fonts, no images, no layout, only the characters themselves. This radical simplicity is exactly why TXT is the most universal and durable format there is: with nothing proprietary to interpret, every text editor, programming tool, and operating system ever made can open it, and will be able to a century from now.

The one piece of complexity hiding inside a TXT file is character encoding, the rule that maps the raw bytes to actual characters. Early text used ASCII (covering basic English letters, digits, and symbols) or regional encodings like ISO 8859-1. Modern text increasingly uses UTF-8, an encoding of Unicode that can represent virtually every character in every writing system, from accented letters to Chinese, Arabic, and emoji, while remaining backward-compatible with ASCII. When a text file shows garbled characters, it is almost always an encoding mismatch: the file was saved in one encoding and opened as another.

The other small detail is line endings. Windows traditionally marks the end of a line with two characters (carriage return plus line feed), while Mac and Linux use one (line feed). This difference is invisible most of the time but occasionally causes a text file to display as one long line or with odd characters when moved between systems. Beyond encoding and line endings, though, there is nothing else to a TXT file, which is the whole point.

Why Plain Text Endures

TXT's lack of features is its greatest strength. Because it stores only characters, it is universally readable, completely future-proof, and extremely small, a text file is as future-proof as a digital file gets, since reading it requires nothing more than knowing the encoding. This is why plain text is the backbone of so much computing: source code, configuration files, logs, data interchange formats like CSV and JSON, and countless notes and READMEs are all just text.

It is also the format of choice when you want content free of any formatting baggage: capturing raw notes, storing data that other programs will parse, or keeping information in a form that will never depend on a particular application to open. Where richer formats lock content into their own structures, TXT keeps it open and portable forever.

When to Use TXT

Use TXT whenever you need pure, unformatted text with maximum portability: notes, code, configuration, logs, simple data, or any content where formatting is unnecessary or actively unwanted. It is ideal when a file must be readable by any tool on any system, now and indefinitely. When you need formatting, headings, styles, or layout, step up to RTF or DOCX; when you need fixed, shareable output, PDF. For everything that is simply text, TXT is the cleanest, most durable choice.

Limitations

TXT's limitations are simply the absence of everything beyond characters: no formatting (no bold, fonts, colors, or styles), no images or media, and no layout. It cannot represent a rich document, only its words. The encoding question can also cause display problems if a file's encoding is unknown or mismatched, which is why UTF-8 is now the recommended default. But these are not really flaws, they are the deliberate trade-off that makes TXT the simplest, most universal, and most enduring format available.