Schema tabs allow definition of source and target schema.
A schema consists of one or more RECORDTYPES. A RecordType consists of FIELDS and VALIDATION RULES.
A field is like a column of a table, along with its name and datatype. Description and Size can be optionally added. In addition to this, a field can have several properties shown in the left pane.
If the source connection defines schema, the schema is locked and the ribbon buttons won’t work. You can still add description to the fields for reference.
For other connectors like Text Delimited and in case of target schemas, user needs to define schemas.
The ribbon bar automatically changes as per schema (source / target) selected.