In one of the previous chapters, we went through some of the examples about the IPC module. In a multi-process architecture model, such as Electron and chromium, it's essential to communicate between the each of the processes. Electron’s IPC module facilitates this communication between the main process and renderer process in a simple yet powerful way; depending on your context, you need to choose between them. For example, in order to communicate from the main process to renderer process, you should use the IPCRenderer module. The IPCMain module should be used if you want to send messages or communicate from the main process to renderer process.

Basically, an IPCMain and IPCRenderer module is an event emitter, which emits the event that can be subscribed in other processes. These modules provide some methods that you can use to send synchronous and asynchronous messages between different processes, in our case, it's main process and renderer process. You will have to use these modules heavily when you working with Electron because Electron’s standard user interface components and some other modules are only available in the main process. So, you will have to send the message to the main process in order to execute these modules.