Stuttgart is very compact, many sights, shopping facilities, restaurants, clubs, bars, cinemas and beer gardens are concentrated on the city centre and a maximum radius of 2km around Schlossplatz. In the centre everything is within walking distance.
In the public transport system (ÖPNV) of the city of Stuttgart there are both light rail vehicles (symbol is a white "U" on a blue background) and suburban trains (symbol is a white "S" on a green background).
The former are operated by Stuttgarter Straßenbahn AG (SSB), the latter by Deutsche Bahn. For you as a passenger, this division of labour makes no difference, as both means of transport are integrated into the Verkehrs- und Tarifverband Stuttgart (VVS). Your ticket is valid for both trains as well as for the bus lines of the state capital.
In addition to these more classical means of transport, there are various other offers in Stuttgart to make it easier for residents and visitors to get around independently of their own car. These include
Bikesharing Regio Rad Stuttgart (rental bike and e-bikes
electrified rental scooters of the Stadtwerke Stuttgart (Stella)
various car sharing offers (such as car2go, Flinkster, stadtmobil)
SSB flex (a kind of call taxi in certain districts)