into a record having the same documentary presentation it manifested when last closed. Each 
digital component requires one or more specific methods for decoding the bitstream and for 
presenting it for use over time. The bitstream can be altered, as a result of conversion for 
example, as long as it continues to be able to fulfil its original role in the reproduction of the 
record. All digital components must be able to work together after they are altered; therefore, all 
changes need to be assessed by t