What is << >> ?

[Tanja Godau]

Hello Erlang Experts,

Could someone please explain to me the purpose of <<>> and how of use it? 

As seen for example in:

=> io:format("   global code:END (of attribute) from ~p~n",[<<?WBXML_END>>]),
    							    ^^          ^^
or
  							 
=> case catch receive_data(Socket,Timeout,Method,<<>>) of
					         ^^^^

Thankyou					       					       
Tanja		 

Tanja

Tanja Godau
Software Designer
Ericsson Eurolab Deutschland GmbH
Verification Tool Design

Tel: +49 2407 575 310 
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