A decoder which decodes input data to generate corresponding decoded output data is operable: (a) to process encoded input data to extract header information indicative of encoded data pertaining to blocks and/or packets included in the encoded input data, the header information including data indicative of transformations employed to encode and compress original block and/or packet data for inclusion as the encoded data pertaining to the blocks and/or packets; (b) to prepare a data field in a data storage arrangement for receiving decoded block and/or packet content; (c) to retrieve information describing the transformations and then applying an inverse of the transformations for decoding the encoded and compressed original block and/or packet data to generate corresponding decoded block and/or packet content for populating the data field; and (d) when the encoded input data has been at least partially decoded, to output data from the data field as the decoded output data.