Tim Bray on the style chosen for writing the HTML5 and WebSockets standards(tbray.org)

   The server must run through the following steps to process the bytes
   sent by the client.  If at any point during these steps a read is
   attempted but fails because the Web Socket connection is closed, then
   abort.

   1.  _Frame_: Read a byte from the client.  Let /type/ be that byte.

   2.  If /type/ is not a 0x00 byte, then the server may disconnect from
       the client.

   3.  If the most significant bit of /type/ is not set, then run the
       following steps:

       1.  Let /raw data/ be an empty byte array.

       2.  _Data_: Read a byte, let /b/ be that byte.

       3.  If /b/ is not 0xFF, then append /b/ to /raw data/ and return
           to the previous step (labeled _data_).

       4.  Interpret /raw data/ as a UTF-8 string, and apply whatever
           server-specific processing is to occur for the resulting
           string (the message from the client).

       Otherwise, the most significant bit of /type/ is set.  Run the
       following steps.  This can never happen if /type/ is 0x00, and
       therefore these steps are not necessary if the server aborts when
       /type/ is not 0x00, as allowed above.

       5.   Let /length/ be zero.

       6.   _Length_: Read a byte, let /b/ be that byte.

       7.   Let /b_v/ be integer corresponding to the low 7 bits of /b/
            (the value you would get by _and_ing /b/ with 0x7F).

       8.   Multiply /length/ by 128, add /b_v/ to that result, and
            store the final result in /length/.

       9.   If the high-order bit of /b/ is set (i.e. if /b/ _and_ed
            with 0x80 returns 0x80), then return to the step above
            labeled _length_.

       10.  Read /length/ bytes.

       11.  Discard the read bytes.

   4.  Return to the step labeled _frame_.

  Data is either framed as a 0xff terminated UTF8 string
  (If the first byte of the frame has a 0 high bit), or as
  a length specified byte array if the first byte has a
  1 high bit. The length is specified using 7 bit variable
  length encoding, with the last byte having a 0 high bit.

  Example: 0x00 | 0x01 0x02 0x03 0x04 | 0xff
  UTF8 string (0x01,0x02,0x03,0x04)

  Example: 0x82 0x03 | 0x55 0xaa 0x55 ... 
  Data length = 0x103, data bytes follow.