What is a .md file and how can I open one?

File extensions quickly tell you what type of file you’re looking at and what program you can open it with. For example, most people know that .jpg files are images and that .docx files can be opened with Microsoft Word. The .md file extension is less familiar, but these files are actually just simple text files. You don’t need any fancy software to open them. Keep reading to learn how to easily open a .md file and what this file type is used for.

A .md file is a plain-text document that contains no other elements. The text can be formatted using special inline text symbols. For example, if you want a word or paragraph to be displayed in bold, you need to type two asterisks before and after it. The ‘MD’ in the .md file extension (also written as .markdown) stands for ‘Markdown documentation’. Markdown is a lightweight mark-up language, and each MD file is written in a particular ‘flavour’ of Markdown. It can be helpful to think of the different flavours as being like different dialects of one language.

With a basic text editor, you can write and edit text in any mark-up language including HTML (Hypertext Markup Language), the language that’s commonly used to create and format websites. However, HTML syntax is difficult for most people to decipher, whereas Markdown text is much simpler and easier to read. On the other hand, Markdown offers fewer formatting options, so it’s only really used for text-only content.

Even if you don’t have any programming knowledge, you probably recognise the .md file extension from the readme file that often comes with new software. Readme files contain important information about the software, sometimes relating to the installation process. You can identify them by their name: readme.md.

Developers and technophiles also use Markdown. For programmers, .md files are a convenient way of archiving and comparing different versions of source code because it’s easier to compare content and identify changes in a mark-up language compared to in a binary format. It’s also easier to convert the files to HTML.

You can open and edit an MD file in any text editor. See below for a list of some well-known programs for Windows and macOS.

The Windows Notepad text editor was created over 30 years ago and remains a simple and fast option. It lets you view and edit files and has a search function too. It no longer comes as a standard part of the operating system in newer Windows versions, but you can download it for free from the Microsoft Store.

Another free app for Windows is Microsoft WordPad. The more advanced word processing program can be used to format and print documents. Notepad++ is similar and is the top choice among most developers because of the availability of lots of plugins to add extra functions.

gVim is a free open-source program that you can download as an app. It has a particularly impressive range of functions, and its user interface makes it easy to work on several documents or MD files at once.

TextMate is a free text editor that’s popular with programmers thanks to its minimalist design and extensive range of features. It supports a variety of programming languages and includes a number of special features which make for even more efficient editing. This includes macro functions which you can use to execute recurring commands more quickly.

MAC users can also use Apple TextEdit to open MD files. This free text editor has some very handy features, such as a built-in spell-checker, table, and list formatting options and the ability to import graphics. It’s a lean application that comes with the Apple operating system as standard.

Last but not least, the open-source program GNU Emacs is available for macOS, Linux, and Windows. It’s a simple text editor and a special favourite among programmers because it has a built-in development environment for compiling, executing, and testing programs.