Generically, metadata is “data about data” — descriptive information that tells you the shape and meaning of other data. In Salesforce, metadata is the configuration of your org — the definitions of objects, fields, page layouts, validation rules, Apex classes, Lightning Web Components, flows, profiles, permission sets, reports, dashboards. It’s what describes how your org works, as opposed to the records (rows in tables) that flow through it.
Metadata vs data
A simple example:
- The Account object is metadata. Its definition — name, fields (
Name,Industry,AnnualRevenue), validation rules, page layouts, sharing model — is metadata. - The actual Account records — “Acme Corp”, “Globex Inc”, “Initech” — are data.
When you create a new field, you’re modifying metadata. When you insert a new record, you’re modifying data. Salesforce keeps both in the same platform but treats them very differently for deployment, change tracking, and the API.
Why metadata is central to Salesforce
Salesforce is a metadata-driven platform. The platform reads each org’s metadata at runtime and renders the customized experience — your fields, your page layouts, your code — on top of the shared multi-tenant infrastructure. Core platform code stays the same for everyone; only metadata varies by org.
This is what enables:
- Seamless three-times-a-year upgrades — your customizations are isolated in metadata, untouched by platform upgrades.
- Sandbox refreshes — copying metadata from production to a sandbox creates a near-identical clone.
- Source-driven development — metadata is just files (XML, code) that can live in Git, be reviewed in pull requests, and deployed via CI.
- Change Sets and the Metadata API — Salesforce’s deployment tools that move metadata between orgs.
Common metadata types
Some of the metadata types you’ll encounter most often:
CustomObject,CustomField,RecordType,Layout,ValidationRuleApexClass,ApexTrigger,ApexComponent,ApexPageLightningComponentBundle(LWC),AuraDefinitionBundle(Aura)Flow,WorkflowRule,ApprovalProcessProfile,PermissionSet,Role,GroupReport,Dashboard,EmailTemplateCustomMetadataandCustomSetting— themselves storage for app-configuration data (often confused with platform metadata)
Quick interview answer
“Metadata is data about data — in Salesforce specifically, it’s the org’s configuration: objects, fields, code, layouts, flows, profiles, permission sets, reports. The platform is metadata-driven, meaning your customizations live as metadata that the multi-tenant infrastructure reads at runtime. This is why upgrades don’t break custom code, sandboxes can be refreshed from production, and we can deploy changes through Change Sets, the Metadata API, or source-driven tools like SFDX.”
Verified against: Salesforce Help — Metadata API Developer Guide and Trailhead — Salesforce Platform Basics. Last reviewed 2026-05-17.