Linker is a program that takes one or more objects generated by a compiler and combines them into a single executable program. Loader is the part of an operating system that is responsible for loading programs from executable (i.e., executable files) into memory, preparing them for execution and then executing them.
Linker is a type of software development tool that accepts one or more object files as inputs and outputs. The linker is thus run after all of the source files have been compiled and assembled into object files. Loader program is an operating system utility that performs the functions of a linker program and then immediately schedules the resulting executable program for action in the form of a memory image, without necessarily saving the program as an executable file. Loader programs are useful for prototyping, testing, and one-off applications.
