Question regarding data type convert between gnuradio blocks

Hi all,
Hope you guys had a great weekend. I have a question about the data type
between gnuradio blocks.
1)I used “stream to streams” block in GRC to de-multiplex the output of
audio source which type is float and drops in the range of (-1,+1), I
was
wondering what is the type of data after “stream to
streams”(de-multiplex)?
In my flow graph, all of the I/O type of blocks in GRC are float,
however,
if I put the data streams into file sinks which input type is also
float,
the data I gathered are hex. Why? I used “Bless” hex editor software to
open
the file. Is that means the “bless” helped me with the type converting?
2) I do need the the bits(or byte) data after demultiplexing for later
digital signal processing, but there’s no ADC in GRC which could help me
with converting the float data between (-1,+1) to bits (byte). How could
I
achieve this conversion?
3) BTW, what is the difference between “stream to streams” and
“de-interleave” blocks. It seems that they have the same outputs.
Thank you very much!
Milo