C30, C60, C90 GO! What does C stand for on audio tapes?

What does the C prefix usually found on audio tapes stand for? And for that matter E prefix on video tapes.

The C on audio cassettes stands for “cassette.” Why the manufacturers thought this necessary, I don’t know.

The E on videotapes stands for “extended” meaning that the tape is suitable for the long play or extra long play settings on your VCR.

Different types of tapes often have different letter codes. These are followed by a number showing the playing time in minutes at the standard playing speed (some tape types have a choice of playing speeds).

In addition, there are model names that vary by manufacturer, like Sony UR and Maxell XL-II and XL-M.

So:
Audio “compact cassettes” (the original name for them) have C. Thus, a 30-minute audio cassette is called a C-30 tape.

I don’t know whether there’s an actual industry standard for these codes (which implies some sort of coordination), or whether it’s simply common usage by a few big manuafcturers.

After digging through Maxell, JVC Canada, and Sony Canada, I find that:

VHS video tapes (in North America anyways) have T.
S-VHS video tapes have ST.
Compact-VHS video tapes have TC.
Compact S-VHS video tapes have STC.
Beta video tapes have L.
mini-DV video tapes appear to have MDV.
8-mm video tapes appear to have P6 or E6, depending on whether they’re metal-particle or evaporated.
DATs (digital audio tapes) appear to have R.
Microcassettes (like those in answering machines) have MC.
Recordable minidiscs appear to have MDW.

The situation with respect to open-reel audio tape and professional products remains unclear to me. Also, there are letter coides for memory sticks (MS) but they’re followed by the capacity in megabytes, not a playing tiome in minutes.

just wanted to add that “Bow wow wow” were cool.
-Luckie