A city has metalled roads with bus or train services for easy travelling.
It supplies potable water through a network of pipelines and electricity to its residents.
There is a sewerage system of drainage of waste water.
There is an authority to look to the sanitation.
There is normally a health centre with qualified doctors to attend to the ailing people.
There are educational and possibly vocational institutions with facility for use of library.
A city is normally a commercial centre.