Birth of the internet
The internet is an incredibly complex system of computers, servers, routers and other hardware linked together by a network of cables, wireless signals and satellites. In the late 1960s and 1970s, it was designed as a decentralised network. The idea was to transmit information quickly and reliably through all those individual computers and servers, without the need for a central node. This method of communication ensures that the network can withstand failures and outages of those nodes.
The technology that ensures this is packet switching: information is split into small packets and sent to the destination via different routes, and then reassembled there.
IANA
In 1988, a non-profit organisation by the name of Internet Assigned Numbers Authority ( IANA ) was established under American law. The IANA was a collaboration between the Information Sciences Institute at the University of Southern California and the US Army's research arm, the Defence Advanced Research Projects Agency (DARPA). This organisation is responsible for developing new technologies for military purposes. However, many innovations have also become of interest to the civilian sector. Besides the internet, DARPA has also helped develop inter alia the GPS, satellite technology and drones.
The core task of the IANA was to assign domain names and IP numbers to network operators. These are people, companies or organisations that design, maintain and manage computer networks. Jon Postel was the main driving force of the organisation from the University of Southern California (USC).
ICANN
In 1998, the Clinton administration decided to scale back the US government's central role in managing the internet and shift it to the private sphere in an international context while maintaining some kind of oversight function for the US government. It set up the Internet Corporation for Assigned Names and Numbers ( ICANN ) as an international non-profit entity, based in the US and thus subject to US law. The contract for the IANA functions by and between the DARPA and USC was then coming to an end. The newly created ICANN logically got those IANA functions (and the contract for them) under its responsibility.
The IANA thus became part of the newly formed ICANN in 1998. Its role was to decentralise the management and allocation of internet resources. It therefore shaped ICANN as an international, multi-stakeholder organisation, in which different stakeholders such as governments, registries, registrars , commercial and non-commercial users have a seat. Everyone's interests are therefore taken into account in the organisation's decision-making and activities.
In 2016, the ICANN created the Public Technical Identifiers (PTI) as a separate entity under its purview. They were contractually bestowed responsibility for managing the IANA functions.