LWC vs. Aura Components
By the end of this lesson, you'll be able to:
- Compare LWC and Aura across performance, syntax, and underlying technology
- Identify when you might still encounter or need to work with Aura
- Explain how LWC and Aura components can interoperate
Prerequisites: "What Is Lightning Web Components?"
A Side-by-Side Comparison
| Aura | LWC | |
|---|---|---|
| Underlying technology | Salesforce's own proprietary framework | Native Web Components (browser standard) |
| Performance | Slower — more framework overhead | Faster — closer to native browser code |
| File structure | .cmp markup + separate Controller.js/Helper.js |
.html template + one ES6 class .js file |
| Learning curve for JS developers | Salesforce-specific patterns to learn | Mostly standard modern JavaScript |
| Salesforce's current direction | Legacy maintenance | Actively invested, default for new work |
Where You'll Still Encounter Aura
- Legacy orgs with substantial existing Aura investment built over years.
- A small (and shrinking) number of older platform features that historically shipped Aura-only.
- Aura sometimes still acts as an outer "shell" around newer components in some older page configurations.
This course focuses entirely on building in LWC — but you should be able to recognize Aura syntax on sight, since real Salesforce projects often involve a mix of both.
LWC and Aura Interoperability
Salesforce deliberately built interoperability between the two: an Aura component can contain and render an LWC component inside it — but not the other way around; an LWC cannot directly contain an Aura component.
This one-directional interop is what lets real orgs adopt LWC incrementally, rather than needing a risky, disruptive rewrite of everything at once.
Recognizing Aura at a Glance
An Aura component's file set looks like: myComponent.cmp (markup, using aura: prefixed tags), myComponentController.js, and myComponentHelper.js — a different shape from LWC's .html + .js + .js-meta.xml set, which Lesson 5 builds firsthand and Module 3 covers in full depth.
Exercise
Given this file list — myComponent.cmp, myComponentController.js, myComponentHelper.js — is this an Aura component or an LWC component? Explain how you know, as a comment.
Show hint
Look at the file extensions and naming pattern.
Exercise
Challenge: an architect asks you to embed a brand-new LWC search widget inside an existing legacy Aura-based page wrapper. Is this technically possible? Explain which direction the interop supports.
Show hint
Recall which component type can contain the other.
LWC vs. Aura Components Quiz
My Notes
Log in to keep private notes on this lesson.
Questions about this lesson
No questions yet — be the first to ask.
Log in to ask a question about this lesson.
Summary
LWC and Aura are both valid ways to build custom Salesforce UI, but they differ significantly in performance and underlying technology — and modern development defaults to LWC, with Aura reserved for legacy maintenance.