Executable and Linkable Format

Executable and Linkable Format (ELF) is a file format used for executables, shared (dynamically linked) libraries, object code and core dumps.

The Wikipedia article has a long list of links to various specifications.

Format info

 * Graphic showing header structure

Software

 * GNU Binutils → objdump
 * GNU Binutils → readelf

Links

 * Executable and Linkable Format
 * ELF101 - a Linux executable walkthrough
 * Hacking GCN via OpenGL (it's got an ELF in it)
 * ELF Hello World Tutorial