Often you need to update the stored procedure packages for a schema.
So you laboriously export them via DDL and pretty them up and then run them on the target schema and then commit them.
Sometimes it's just easier to export the schema as an Oracle dump (which includes all the related stored procedures) and then import them on the target schema.
An example of the export command is:
exp login/password@schema file=target file directory/export name.dmp