AngularTemplate-driven Forms khai báo nhiều logic trong template qua ngModel, dễ dùng cho form nhỏ.
Reactive Forms tạo form model rõ ràng trong TypeScript bằng FormControl, FormGroup, FormArray, phù hợp form phức tạp, dynamic fields, validation nhiều tầng và unit test. Rule thực tế: form đơn giản dùng template-driven được; business form quan trọng nên dùng reactive.
Template-driven Forms put much of the logic in the template through ngModel, which is easy for small forms.
Reactive Forms create an explicit TypeScript form model with FormControl, FormGroup, and FormArray, fitting complex forms, dynamic fields, multi-layer validation and unit tests. Practical rule: simple forms can use template-driven; important business forms should use reactive forms.