Linker is a computer program that takes one or more object modules generated by a compiler and combines them into a single executable application. It can also combine libraries of precompiled code with the object code to create complex applications. Linkers are necessary to create executables in various file formats, and use memory management functions to assign executable code and data to system memory, so that applications can run.
Linkers are often used in conjunction with a linker script, which is an input file that provides the linker with specific instructions on how to make an executable. Linker scripts are most commonly written in a text-based scripting language, and are supported by most compilers and linkers.
Linkers are also responsible for linking dynamic and static libraries, or code blocks that can be shared by multiple applications. The linker processes these dynamically-linked libraries, and packages them with the application code during the linking process. Once complete, the application is ready to be run.
Linkers are important components of any programming language development process. They not only allow developers to create complex applications, but they also help the developers to optimize code for different memory configurations, and to link code written in different languages.
