Video streaming services deliver films, series, live television and sometimes sport or news over the internet, funded by subscriptions, advertising or public broadcasting. Households use them for entertainment; organisations meet the category as rights holders and buyers of licences, and when staff and customers watch on company devices or in hotels, waiting rooms and shared spaces.
The sovereignty side is cultural as much as technical. A platform decides which titles are available, in which languages and with what prominence, so a handful of services can shape what a large audience sees. Reference points such as Netflix, Disney+ and Amazon Prime Video are operated by US-headquartered companies, which makes the rules on international transfers relevant to account and viewing data. Your history is hard to move: data portability gives you a copy of what you provided, but not your recommendations, profiles or library.
When considering a European option, check who owns the service and whether it is run by a public broadcaster or a private company, how viewing data is used for profiling and advertising, and whether the service works with minimal tracking.