The decision tree is straightforward once you know what each type does. Pick the type that matches the use case; mixing types creates complexity.
- Custom UI component
Use Lightning Web Component for new builds. Aura only for maintenance of existing components.
- Top-level app
Create a Lightning App via App Manager. Configure brand, navigation, utility bar.
- Custom record-page layout
Build a Lightning Record Page in Lightning App Builder. Assign to record types and profiles.
- Custom home or app page
Build a Lightning Home Page or App Page in Lightning App Builder.
- Branded email template
Build a Lightning Email Template in the Lightning Email Template designer.
- Embed Lightning in external page
Use Lightning Out App; create the App, embed via script tag on the external host.
Gotchas
- Aura is supported but on a long-term sunset path. New builds should use LWC.
- Lightning Bolt as a brand is effectively retired. Pick Experience Cloud Templates or Industries Cloud for new builds.
- Each Lightning Type ships as distinct metadata. Mixing types in one feature requires understanding each one''s deployment model.
- Classic alternatives (Visualforce, Classic Apps, Classic Email Templates) are still supported but should not be used for new work.