This is how the raw data is stored. sometimes its readable.. like what you put into the stream.
The hex you find at the top of a json call under a property named HEX is the raw hex of JSON. Copy your transaction hex and paste it into a hex to ascii decoder - something like http://www.rapidtables.com/convert/number/hex-to-ascii.htm
You wont need this usually as the raw hex is already the json you get back (with a few differences)
Your custom fields and data you add to transactions are also encoded to hex and you can do the same thing, converting it.
consider the following:
"type": "stream",
"name": "Item",
"streamref": "20-265-54584",
"publishers": ["1DpvKsVyF37NMGhwowenKKrRT8Hi92HZZT8t9J"],
"key": "Property",
"data": "7b22746f6b656e223a2250412d636465633264723230333261663134227d"
the data can be transformed back to what you put in.
{"token":"PA-cdec2dr2032af14"}