Editing External Data Representation (section)

{{Short description|Data serialization format}}
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'''External Data Representation''' ('''XDR''') is a [[technical standard|standard]] [[data serialization]] format, for uses such as [[computer network]] protocols. It allows data to be transferred between different kinds of computer systems. Converting from the local representation to XDR is called ''encoding''. Converting from XDR to the local representation is called ''decoding''. XDR is implemented as a software library of functions which is portable between different [[operating system]]s and is also independent of the [[transport layer]].

XDR uses a base unit of 4 bytes, serialized in [[big-endian]] order; smaller data types still occupy four bytes each after encoding. Variable-length types such as string and opaque are padded to a total divisible by four bytes.  [[Floating-point number]]s are represented in [[IEEE 754]] format.