What is the Darknet and what happens there?

The term “darknet” is usually directly associated with crime in the public mind. However, very few people know what exactly this word means, what functions and structures it denotes – and even if a different impression can easily arise: according to our jurisdiction, neither surfing nor operating sites on the darknet are illegal per se. On the contrary, the infrastructure of the darknet is also used for purposes that are not only in line with democratic law, but can even prove to be important instruments for strengthening democracy, preserving individual freedom and protecting privacy. Corresponding arguments come up again and again in debates about possible interventions or even a de facto ban of the “anonymous internet”. So does the darknet simply have “bad” and “good” sides? And do we have to live with the fact that this technology, as long as it serves whistleblowing, political opposition or good journalism, also fosters serious and most serious crime?