A Directorate-General (abbr. DG) is an administrative branch dedicated to a specific field of expertise (e. g. agriculture). It is very similar to a ministry, but we can’t call them like that or member states will be scared that the EU wants to take over their sovereignty.

The head of a DG is a Director-General (also abbreviated as DG, just to make things clearer). A DG is made of Directorates, a Directorate is made of Units, big Units are divided into Sectors.