Tokyo’s 23 Special Wards
Tokyo consists of 23 special wards and 39 other, ordinary municipalities.
Together, the 23 wards constitute metropolitan Tokyo, whereas the other municipalities of Tokyo prefecture tend to get progressively more suburban/rural the further you get from the center.
The central Tokyo government provides some shared services for all of Tokyo prefecture, such as water supply and fire services
The 23 special wards have their own elected officials and administrative offices that manage and provide many public services impacting the day-to-day lives of ward residents, such as waste disposal, public daycare, seniors services and the like
Residents (especially longtime residents) often have a lot of ward pride! Sometimes the wards may even ‘reward’ longevity in living within the ward (e.g. parents who themselves were born and raised within a ward get a higher score when applying for daycare for their children)
The wards vary greatly in terms of population. As of 2020, Chiyoda-ku (the most central ward housing the Imperial palace as well as financial and political centers) had a population of just 67K people, while Setagaya-ku was the most populous with a population 943K people.
Select sources: Wikipedia, Tokyo Metropolitan Government, Japan Local Government Center