The Executable and Linkable Format (ELF) is a common standard file format for executables, object code, shared libraries, and core dumps. It is used on many Unix-like operating systems, including Linux, Solaris, FreeBSD, and others. ELF files are designed to be flexible and extensible, allowing for a variety of architectures and operating systems to use the same basic format. The format consists of a header, program headers, section headers, and the data itself. The header describes the overall structure of the file, including the entry point for execution. Program headers describe segments, which are contiguous regions of the file that are loaded into memory during execution. Section headers describe sections, which are used for linking and debugging. The data itself contains the actual code and data of the program. ELF files can be statically linked, meaning that all of the necessary code is included in the executable file, or dynamically linked, meaning that some of the code is loaded from shared libraries at runtime. This allows for smaller executable files and easier updates to shared libraries.