The illustration below shows how the European Data Protection Board is composed, how its management (Chair and 2 Deputy Chairs) looks like and gets elected as previously explained, what role it plays and how it can perform that role.
So, to summarize: the European Data Protection Board consists of:
• The head of each national DPA of each member state (remember that there can be several supervisory authorities per member state but there can only be one in the EDPB, this is in particular de facto the case for Germany).
• The European Data Protection Supervisor or EDPS.
• The European Commission which has no voting rights in the EDPB though.
The main role of the EDPB is to:
• Ensure consistent application of the GDPR (and other data protection laws in the framework of the data protection law reformation in the EU).
• Make sure that DPAs cooperate (de facto also with that consistency in mind but also as in several cases cooperation simply is needed).
The key means the European Data Protection Board has to fulfil its role are:
• Binding decisions (which is a new mechanism in the GDPR, for example in the scope of settling disputes regarding international personal data transfers).
• Opinions (e.g. regarding the compliance of a draft code of conduct on a sector level).
• Guidelines (so, WP29 Guidelines in the future simply are EDPB Guidelines).