According to dictionary.com:
sky·line
–noun (Also, sky line.)
1. the boundary line between earth and sky; the apparent horizon: A sail appeared against the skyline.
2. the outline of something, as the buildings of a city, against the sky: the New York skyline.
From Wikipedia, the free encyclopedia:
A skyline is best described as the overall or partial view or relief of a city's tall buildings and structures consisting of many skyscrapers. It can also be described as the artificial horizon that a city's overall structure creates. Skylines are a good representation of a city’s overall power; the more prominent the skyline, the more money the city has to spend. Skylines also serve as a kind of fingerprint of a city, as no two skylines are alike. Skylines that are stretched out to a large (sometimes panoramic) view because of large cities or twin cities are called cityscapes. In many but not all metropolises, skyscrapers play a significant role in defining the skyline. In more strongly planned metropolises (such as Minneapolis), the skyline tends to form the shape of an artificial mountain, with the tallest buildings toward the center of town.
Types of skyline views
Daytime: A normal, generally widestretched view of a city's skyline that is during the daytime. Sometimes used during dawn and dusk to use the setting and rising sun in the background.
Silhouette: A skyline where buildings are blended together as one black shape that usually includes only one layer of the skyline.
Nightime: A skyline during the nightime. What one sees of buildings is mainly the lighting inside, and sometimes illumination on the outside, for eye candy or advertising. For cities on lakes and oceans the reflective water adds to the view, and is also commonly used in pictures.
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