A file's data encoding specifies how to interpret the basic objects in a file. Class ELFCLASS32 files use objects that occupy 1, 2, and 4 bytes. Class ELFCLASS64 files use objects that occupy 1, 2, 4, and 8 bytes. Under the defined encodings, objects are represented as shown below. Byte numbers appear in the upper left corners.
Encoding ELFDATA2LSB specifies 2's complement values, with the least significant byte occupying the lowest address.
Encoding ELFDATA2MSB specifies 2's complement values, with the most significant byte occupying the lowest address.