Urbanisation has different historical processes - from Europe to the colonised and new lands of USA to the colonised old Asian and African continent. How urban planning happened in New York is very different from New Delhi or London. 

Urban planning is derided nowadays under a neo liberal free market discourse - for not allowing cities to grow and attract capital and investments. The criticism is based on a false ahistorical propaganda that cities could all be planned in a grid structure like New York and some other cities in USA.

Sharing the few videos here that show why and how urban planning resulted in different outcomes.

• Grids – New York www.myleszhang.org/here-grows-new-york-city/
• Circular
– concentric rings – London www.theguardian.com/cities/2014/may/15/t...-year-history-mapped
- Delhi edtimes.in/watch-evolution-of-delhi-from...w-delhi-in-pictures/ sarmaya.in/spotlight/delhi-evolution-of-a-city/
Sectors – sectoral, wedge shaped within circular
• Multiple nuclei 
• Irregular pattern