1. A method of operating a process, comprising: determining an execution application; generating an application process for the determined execution application; loading the determined execution application from a secondary memory to a primary memory in the generated application process; generating a platform child process that is a child process of a platform process configured to operate the loaded application; and loading a previously set sub-module of the application to the platform child process from the application process, wherein the application is composed of a main module and the sub-module, each of which is operable in a separate process, wherein the application process, the platform process, and the platform child process are generated and managed by at least one processor configured to execute a process management module, wherein the application process executes communication with the sub-module loaded in the child platform process, wherein the platform child process has a priority identical to the platform process, and wherein the loaded application is executed by operating the application process and the platform child process.