Urban planning is a mixture of science and art. It encompasses many different disciplines and brings them all under a single umbrella. The simplest definition of urban planning is that it is the organization of all elements of a town or other urban environment. However, when one thinks about all the elements that make up a town, urban planning suddenly seems complicated - and it is.

Real urban planning is a relatively new concept. It gained popularity beginning in the mid-to-late 19th century, when it became obvious that there should be some kind of plan or larger goals for the growth of big cities like New York and Philadelphia. Before this time, cities very often grew as they had need, and the surrounding land was just swallowed up. London, Paris, Tokyo - none of these world cities had much urban planning, and even now, the addresses and streets in their older sections can be confusing even to natives.

Urban planning also became popular because of the growing need to get factory workers into healthier housing, rather than stuffing them into fire-trap tenements. With the advent of unions, workers had advocates to help lobby for better housing. Hence, "mill villages" and "steel villages" sprang up in larger cities.

Nowadays, urban planning takes all aspects of a city into consideration. It includes plans for safety, aesthetics and common sense placement of everything from houses to factories. Parents wouldn't want their children's playground next to the water treatment plant, for instance, and urban planning helps eliminate such problems. Goals for attractive architecture for city buildings are put into place and pleasing green spaces are planned. Good urban planning gets schools into the neighborhoods where they are needed most, places hospitals in centralized locations, allows for growth and plans highways accordingly.

Perhaps good urban planning is most evident in good highway planning in a city. Anticipating growth and traffic needs for a big city is crucial. Urban planners must consider how future growth will affect traffic flow and try to eliminate trouble spots before they become a problem. Even placing sewer systems and drainage systems is a necessary element of urban planning, albeit a less glamorous one. Urban planners must consider geography, the water table and numerous other elements of a city's landscape in order to properly plan for this necessity.

Because so many disciplines make up the larger concept of urban planning, a group of urban planners may have widely divergent degrees: civil engineering, architecture, botany, landscape design, electrical engineering, business administration, and so on. Urban planners who are good at what they do are highly sought after by municipal governments. When efficient urban planning is used, cities are more attractive and serve their citizens to the best of their potential. 

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