What is the difference between computed() signals and standard method/getter calls in templates?

Q: What is the difference between computed() signals and standard method/getter calls in templates?

**Core concept.** A ** computed() ** signal creates a read-only dependency that caches its computed value and recalculates **only** when its input signals change. Conversely, template method calls or getters evaluate **on every single change detection cycle**, creating massive CPU overhead for heavy logic. ### computed() vs Getters/Methods | Metric | computed() Signal | Template Getter / Method | | --- | --- | --- | | Evaluation | Lazy (only when accessed) | Eager (on every change detection check) | | Caching | Yes (memoized value) | No (recomputes every time) | | Dependency tracking | Automatic | None | | Performance | High, constant time O(1) | Can cause lag if doing complex calculations | > **Interview tip:** Explain that because standard Angular change detection is triggered by mouse moves, clicks, timers, and HTTP requests, a simple getter or method inside a template might execute hundreds of times a minute. Replacing these with computed() signals provide

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**Core concept.** A **computed()** signal creates a read-only dependency that caches its computed value and recalculates **only** when its input signals change. Conversely, template method calls or getters evaluate **on every single change detection cycle**, creating massive CPU overhead for heavy logic. ### computed() vs Getters/Methods | Metric | computed() Signal | Template Getter / Method | | --- | --- | --- | | Evaluation | Lazy (only when accessed) | Eager (on every change detection check) | | Caching | Yes (memoized value) | No (recomputes every time) | | Dependency tracking | Automatic | None | | Performance | High, constant time O(1) | Can cause lag if doing complex calculations | > **Interview tip:** Explain that because standard Angular change detection is triggered by mouse moves, clicks, timers, and HTTP requests, a simple getter or method inside a template might execute hundreds of times a minute. Replacing these with computed() signals provide

What is the difference between computed() signals and standard method/getter calls in templates?

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