The irregular street layout of lower manhattan – a legacy of dutch settlement during the 17th century – contrasts sharply with the 19th century grid system instituted by later inhabitants, which covers the rest of manhattan. this is an example of

The change in the layout of the grid system is an example of urban planning and development.

Explanation:

Urban planning and development takes into consideration the layout of a city or town and plans a layout of all the essential amenities and facilities required in the area. With urban planning and development, the city or town is divided into several small areas and the planning takes place in stages.

Urban planning and development also takes into consideration the factors like movement of people, layout of houses, types of houses and other such factors that have an impact in how a town or city is planned for the maximum benefit of people.