What is MIME type "text/x-nh"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

text/x-nh is a MIME type for plain text files that use the Newick tree format.

This format represents tree structures using nested parentheses, commas, and optional branch lengths. It is popular in bioinformatics for describing evolutionary relationships.

These files are simple and can be viewed with any text editor. They allow software to quickly parse and display tree data.

Files in this format typically use the TREE extension. The "x-" prefix indicates it is a non-standard type.

Use in Phylogenetics: Represents evolutionary or phylogenetic trees.
Lightweight: Provides a simple, text-based way to store complex tree data.
Software Compatibility: Read by analysis and visualization tools in computational biology.

Learn more about the Newick tree format on Wikipedia.

Associated file extensions

.tree

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: text/x-nh

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="text/x-nh">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'text/x-nh');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.tree

FAQs

What is the text/x-nh MIME type used for?

The text/x-nh MIME type is used to identify files containing phylogenetic trees formatted in the Newick notation. These files are essential in bioinformatics for representing evolutionary relationships between organisms using a specific text-based structure of parentheses and commas.

How do I open a file served as text/x-nh?

Because the underlying format is plain text, you can view the raw data using any text editor like Notepad, Vim, or TextEdit. To visualize the actual tree structure graphically, you will need specialized software such as FigTree, Dendroscope, or online phylogenetic tree viewers.

How do I configure Apache to serve .tree files correctly?

You can map the .tree extension to this MIME type by adding a directive to your .htaccess or main configuration file. Use the line: AddType text/x-nh .tree to ensure the server sends the correct Content-Type header.

Why does my browser download the file instead of displaying it?

Browsers do not have built-in rendering engines for Newick tree data, so they often treat text/x-nh as an unknown binary file and trigger a download. To force the browser to show the raw text, you can configure your server to send the header Content-Disposition: inline.

What does the 'x-' prefix mean in text/x-nh?

The x- prefix indicates that this is a non-standard or experimental MIME type that is not officially registered with the IANA. It is a convention used to define private or community-specific types, such as those used in scientific research software.

Are there other file extensions associated with this MIME type?

While .tree is common, Newick files often use the extension .nwk or .newick. Since text/x-nh is non-standard, these extensions might sometimes be served as text/plain or application/newick depending on the server configuration.

Is text/x-nh compatible with Nginx?

Yes, Nginx can serve this type, but you must manually define it in your mime.types file or server block. Add the line text/x-nh tree; inside the types { ... } block to associate the MIME type with the file extension.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.