My apologies; I didn't explained my problem correctly.
Initially I have a simple application created with Angular/cli.
joke.component.ts in src/app/jokes (I want a separate folder for the functionality,jokes)
I use tag 'joke' in app.component.ts as follows
I am not importing joke.component.ts because I have imported and declared it in app.module.ts
What I am seeing is that anything imported and declared in app.module.ts is available to other components (In this case app.component).
For a large program with multiple functionality, I want to create components for different functionalities in separate folders. What I don't want is to import every component in app.module.ts; For every functionality I want to create a module like joke.module.ts
In this module I import and declare the components for the functionality and I was hoping that importing and declaring these modules in app.module.ts would work, but It didn't.