type and content type [application/octet-stream]

The MIME type "application/octet-stream" is a generic binary file type. It denotes that the content of the file is binary data that cannot be interpreted as text. This MIME type is often used when the specific type of data is unknown or when the content needs to be treated as a binary stream, such as in file transfers.

For example, when downloading a file from the internet, the web server may send the file with a content type of "application/octet-stream" to indicate that the file is binary data and should be saved to disk rather than displayed in the browser. Similarly, some email clients may use this MIME type for file attachments that are not recognized as a specific file type.

Overall, "application/octet-stream" is a catch-all MIME type for binary files that do not fit into more specific categories.