cdata and \u encoded and unicode and base 64 encoded text utf8 and utf32

An important point about CDATA is that it is NOT an encoding, but is effectively the same text characters used in XML which may look like XML but isn't. Therefore you cannot use characters from an encoding which are NOT allowed in normal XML. The text enclosed in CDATA "brackets" can look like XML but it will not be interpreted as such.

looks some deep concept. any good free video tutorials around this concepts. please advise

Well, as I think you can see from above that UNICODE chracter encoding is a none-trivial issue. IMO what I wrote should answer many of your questions from above. If you have problems with some details or particular points please feel free to ask.

I'm not sure if there's simply such one good video (in fact I don't like video tutorials for such things, because I have my own learning rate, and because there's no cut-and-paste ;o) - unfortunateley I can't tell you about other tutorials than those everyone can find, i.e. via Google: https://www.google.de/search?q=unicode+video+tutorial

Besr regards,

ZOPPO

AFAIK for JSON it's even possible to use UTF-8, UTF-16 and UT-32 (where UTF-8 is the default), but there's no kind of defining code like in XML, instead it simply uses the encoding of the text-file (see declaration of BOM above at 1.).

in json how we specify different typease like UTF-8/UTF-16/UTF-32/UTF-64 etc

is it UT-32 or UTF-32 is there any difference?

Difference? I don't understand all of these abbrieviations which aren't standard.

As far as JSON is concerned, if it is the response to an HTTP request, it'll be in the mine-tye as to whether JSON is ANSI/UTF-8/UTF-16.
If it is Node.js it will almost always be UTF-8, otherwise a file BOM will be present, or on Linux it's mostly UTF-8 on Windows ANSI.