Open APPLICATION-OCTET-STREAM File

Files interchangeable over the internet are divided into two large groups:

text / plain: it is the default value for text files and it must be readable, normally, by any office application, and therefore cannot contain binary data.

application / octet-stream: is the value given for all other cases including unknown file types.

These classifications are framed within the MIME (Multipurpose Internet Mail Extension) conventions that are nothing more than specifications aimed at the exchange of all types of files, regardless of their extension, and in a transparent way for the user. The application / octet-stream subtype tells the browser / mail client that the file is of binary type and has a couple of parameters defined, as follows:

• Type: the general type of binary data, for purposes of automatic processing, as well as treatment by humans.
• Padding: the number of padding bits to be appended to the content bitstream. When the total number of bits is not a multiple of 8, possible errors are corrected with this parameter.

An important note you should consider is that modern browsers are designed to take particular care when handling these files, trying to protect the user from dangerous behavior.