What is the core task of the media, and what specific functions does it serve?

To hold up a mirror of reality to the public — by informing, helping people form opinions, acting as a watchdog and offering criticism, all in the service of finding the truth.

The overarching job is to give the public an accurate picture of reality (German: ein Abbild der Realität). That breaks down into several concrete functions:

• Inform — report what is actually happening.
• Opinion-forming (Meinungsbildung) — give people the facts and context they need to make up their own minds, not tell them what to think.
• Control function / watchdog (Kontrollfunktion) — scrutinise the powerful (government, business, institutions) and surface wrongdoing.
• Criticism — question and challenge, rather than simply relay.

All of this is bound to one purpose: the search for the truth, reported in a way that is fair and factually accurate (sachgerecht).

Tip: The watchdog role is why the press is often called the "fourth estate" — a check on power that sits alongside the legislative, executive and judicial branches.