Preloading modules in Angular is similar to lazy loading, but the modules will be loaded immediately after all the eager loaded modules are ready. This eliminates the possible latency when navigating to a lazy-loaded module in case if you don't have a preloading setup for it.
Official docs:
https://angular.io/api/router/Preload...
Code: https://github.com/stevermeister/Angu...
Angular Pro Screencasts Roadmap - https://github.com/stevermeister/Angu...
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