What is MIME type "application/x-compressed-iso"?

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

The MIME type application/x-compressed-iso labels files that hold compressed disk images. This means an original ISO image is stored in a smaller, compressed format while keeping its structure intact.

It is commonly used when backing up or emulating optical media. Software that reads these images must support the compression. The technique helps save space and speeds up loading times in many cases.

Main use: Efficient backup of optical disc images.
Emulation: Supports systems like game console emulators that load disc images.
Ensures the original file system structure is preserved in a compressed format.
Reduces file size without sacrificing the ability to mount or run the image.

Files marked with this MIME type usually carry extensions such as CSO, CISO, or WBI. These links provide more details on each specific format.

Associated file extensions

.cso, .ciso, .wbi

Usage Examples

HTTP Header

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


    Content-Type: application/x-compressed-iso

HTML

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


    <a href="file.dat" type="application/x-compressed-iso">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', 'application/x-compressed-iso');
      res.end('Content here');
    }).listen(3000);

Associated file extensions

.cso, .ciso, .wbi

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.