What is MIME type "application/x-shockwave-flash2-preview"?

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

application/x-shockwave-flash2-preview is a non‐standard MIME type used mainly to indicate a preview version of Flash multimedia files.
It is tied to the Adobe Flash technology and is a variant of the common Flash MIME type.
Files with this type often use the format SWF, a format used for interactive animations and multimedia content.

Main Use: Marks a preview mode for Flash content so that software can treat it differently from a full Flash file.
Other Uses: Provides a quick look at rich media without loading all interactive elements.
It also helps some applications to generate thumbnails or brief previews before engaging full Flash functionality.
Key Facts: The prefix "x-" signals that this type is experimental or non-standard.
It ties closely to legacy systems and applications that handled Flash content in a specialized preview manner.

For extra technical details, see the entries on MIME types and the legacy usage of SWF files.

Associated file extensions

.swf

Usage Examples

HTTP Header

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


    Content-Type: application/x-shockwave-flash2-preview

HTML

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


    <a href="file.dat" type="application/x-shockwave-flash2-preview">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-shockwave-flash2-preview');
      res.end('Content here');
    }).listen(3000);

Associated file extensions

.swf

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.