Field Data having string in binary

Hi All,
I am trying to check how Paraview writes the field data having string in binary. My field data is
FIELD FieldData 1
VCNAME 1 259200 string
HardBrick-ID0 …

It works in ascii. When I use Paraview to convert it to binary, I get “ÍHardBrick-ID0ÍHardBrick-ID0…”. What is the first character that is written? Is it the size? If so, what is the type (int/ unsigned int etc.)?
Thank you