Suggest an editImprove this articleRefine the answer for “How does DI help with application modularity?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**DI** makes an application modular because it separates the logic of creating dependencies from using them. Components and services become independent: they can be easily changed, moved, or tested separately. **Key point:** DI separates *what* a class needs from *how* that is created and managed.Shown above the full answer for quick recall.Answer (EN)ImageDI makes an application modular because it **separates the logic of creating dependencies from using them**. Components and services become independent, they can be easily changed, moved, or tested separately. ### Point by point: 1. **Each module manages its own dependencies.** In Angular you can specify which services are available only within a specific module, which isolates them from the rest of the application. 2. **Code reuse.** The same service can be used in different modules without duplication, DI figures out on its own where and how to create it. 3. **Easy swapping of implementations.** If you need to change how a service works (for example, replace a fake with a real API), it is enough to register a different implementation, the component's code stays the same. 4. **Painless testing.** You can substitute a test dependency for the real one, DI swaps it in automatically when the test runs. **Summary:** DI helps make an application flexible and modular because it separates: - *what* a class needs, - and *how* that is created and managed.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.