There are two things you can paste into a text field: text and formatting. Most of the time you want the first and get the second, which is why a paragraph copied from a word processor turns up in an email as a wall of odd spacing, smart quotes, and a stray heading that is now the same size as everything else.
Understanding the difference between plain text and rich text solves a surprising number of daily problems, and it takes about five minutes.
What plain text actually is
Plain text is characters and nothing else. Letters, numbers, punctuation, spaces, line breaks. No bold, no italic, no font, no colour, no paragraph spacing. Every character is the same size and weight.
The advantage is universality. A plain-text file will open on any device, in any program, in any decade. It cannot be corrupted by a missing font or a lost stylesheet. It is the closest thing digital writing has to a durable format.
The disadvantage is that it cannot express structure. You cannot make a word bold in a .txt file, because there is nothing in the format to hold that information.
What rich text actually is
Rich text is characters plus a set of invisible instructions about how they should look. Bold, italic, size, colour, alignment, spacing, hyperlinks, tables, images. When you copy from a word processor or a web page, the clipboard usually carries both the characters and the instructions.
That is why pasting into a plain-text field produces a mess. The field cannot interpret the instructions, so it either strips them (best case) or converts them into visible symbols (worse case), and you end up with text that looks like it survived a fire.
The fix is to paste as plain text. On Windows, Ctrl+Shift+V in most browsers and many apps; on a Mac, Cmd+Shift+V or Cmd+Option+Shift+V depending on the app. If the app does not support it, paste into a plain-text editor first, then copy from there.
Where plain text wins
Code and configuration. Always plain text. Rich-text formatting in a code file is a syntax error waiting to happen.
Email bodies for important messages. A plain-text email cannot break in a client that does not render HTML, and it cannot carry a tracking pixel or a hidden style. It is also read as more personal, which is useful when the message matters.
Archives. If you want a document to survive, keep a plain-text copy. Formats change; characters do not.
Forms and pasted content. Web forms, search boxes, and database fields usually accept plain text only. Pasting rich text into them is the most common cause of "why does my input look wrong" problems.
Collaboration with strangers. When you do not know what software the other person has, plain text is the only format guaranteed to arrive intact.
Where rich text wins
Anything with structure. Headings, lists, tables, and emphasis carry meaning, and stripping them makes a document harder to read, not easier.
Documents meant to be printed or presented. Layout matters, and plain text has no layout.
Web content. HTML is a rich-text format, and it is the right one for anything published on a page.
Anything a non-technical reader will open. A .docx or a PDF opens with a double-click. A .md file may open in a text editor full of symbols, which is not what most readers expect.
Markdown: the useful middle
Markdown is plain text with a small set of conventions for structure. A line starting with # is a heading. Text between ** is bold. A line starting with - is a list item.
The advantage is that a Markdown file is readable as plain text and convertible to rich formats. You can write in any editor, store the file anywhere, and generate HTML later. The Markdown guide covers the syntax, and the Markdown to HTML converter turns it into a web page.
For writers, Markdown is often the best of both worlds: the durability of plain text with enough structure to be useful.
The everyday problem: pasting from a word processor
Here is a routine that solves the most common formatting headache in about ten seconds.
- Copy the text from the word processor.
- Paste it into a plain-text editor, or use paste-as-plain-text.
- Copy it from there.
- Paste into the destination.
If the text has already arrived with junk — smart quotes, doubled spaces, stray tags — the text cleaner strips most of it in one pass. For anything that came from a web page and still carries HTML markup, the HTML tag remover leaves just the words.
File formats and the long view
If a document matters, keep it in more than one format. A reasonable archive policy for most writers:
- The working version in the format the tool requires (docx, md, or whatever the editor asked for).
- A PDF of the final version, so the layout is preserved.
- A plain-text copy of the words, so the content survives a change of software.
The third one is the one people skip and the one that saves them years later. A plain-text file from 1998 still opens. A word processor file from 1998 may not.
Choosing in one question
Ask: does the reader need to see the structure, or only the words?
If structure matters, use a rich format. If only the words matter, use plain text. Everything else follows from that.
The corollary is that most content is words first and structure second. Write in plain text if you can, add structure deliberately, and strip the formatting when you move between tools. The text is the part that lasts.