Editing Object file (section)

{{short description|File containing relocatable format machine code}}
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An '''object file''' is a [[Computer file|file]] that contains [[machine code]] or [[bytecode]], as well as other data and [[metadata]], generated by a [[compiler]] or [[Assembler (computing)|assembler]] from [[source code]] during the compilation or assembly process. The machine code that is generated is known as [[object code]].

The object code is usually [[Relocation (computing)|relocatable]], and not usually directly [[executable]]. There are various formats for object files, and the same machine code can be packaged in different object file formats. An object file may also work like a [[shared library]].

The metadata that object files may include can be used for linking or debugging; it includes information to resolve symbolic cross-references between different modules, [[relocation (computing)|relocation]] information, [[stack unwinding]] information, [[Comment (computer programming)|comments]], program [[symbol (computing)|symbols]], and debugging or [[profiling (computer programming)|profiling]] information. Other metadata may include the date and time of compilation, the compiler name and version, and other identifying information.

The term "object program" dates from at least the 1950s: {{quote|A term in automatic programming for the machine language program produced by the machine by translating a source program written by the programmer in a language similar to algebraic notation.<ref name="Wrubel_1959"/>}}

A [[linker (computing)|linker]] is used to combine the object code into one executable program or library pulling in precompiled system libraries as needed.