What is metadata in Salesforce?

Metadata in Salesforce is basically "data that describes other data".

For example, in Salesforce you can query data like this:

      SELECT FirstName FROM Contact WHERE FirstName='Mike'

Salesforce also provides metadata tables that describe code and configuration:

    SELECT Id FROM ApexClass WHERE ApiVersion < 25>

The Metadata API provides even more detail about code, objects, profiles, reports, and many more items http://www.salesforce.com/us/developer/docs/api_meta/index.htm


The Force.com IDE for Eclipse plug-in uses the Metadata API to keep local files in sync with Salesforce.