What's the difference of ContentType and MimeType

Question

As far as i know, they are absolute equal. However, browsing some django docs, i've found this piece of code:

HttpResponse.__init__(content='', mimetype=None, status=200, content_type='text/html')

wich surprise me the two getting along each other. The official docs was able to solve the issue in a pratical manner:

content_type is an alias for mimetype. Historically, this parameter was only called mimetype, but since this is actually the value included in the HTTP Content-Type header, it can also include the character set encoding, which makes it more than just a MIME type specification. If mimetype is specified (not None), that value is used. Otherwise, content_type is used. If neither is given, the DEFAULT_CONTENT_TYPE setting is used.

However, i don't find it elucidating enough. Why we use 2 different naming for (almost the same) thing? Is "Content-Type" just a name used in browser requests, and with very little use outside it?

What's the main difference between the each one, and when is right to call something mimetype as opposed to content-type ? Am i being pitty and grammar nazi?

Answer 1

Why we use 2 different naming for (almost the same) thing?

Backwards compatibility, based on your quote from the documentation.

Answer 2

Why we use 2 different naming for (almost the same) thing? Is "Content-Type" just a name used in browser requests, and with very little use outside it?

What's the main difference between the each one, and when is right to call something mimetype as opposed to content-type ? Am i being pitty and grammar nazi?

The reason isn't only backward compatibility, and I'm afraid the usually excellent Django documentation is a bit hand-wavy about it. MIME (it's really worth reading at least the Wikipedia entry) has its origin in extending internet mail, and specifically SMTP. From there, the MIME and MIME-inspired extension design has found its way into a lot of other protocols (such as HTTP here), and is still being used when new kinds of metadata or data need to be transmitted in an existing protocol. There are dozens of RFCs that discuss MIME used for a plethora of purposes.

Specifically, Content-Type: is one among several MIME headers. "Mimetype" does indeed sound obsolete, but a reference to MIME itself isn't. Call that part backward-compatibility, if you will.

[BTW, this is purely a terminology problem which has nothing whatsoever to do with grammar. Filing every usage question under "grammar" is a pet peeve of mine. Grrrr.]

Answer 3

If you want to know the details see ticket 3526.

Quote:

Added content_type as an alias for mimetype to the HttpResponse constructor. It's a slightly more accurate name. Based on a patch from Simon Willison. Fully backwards compatible.