Photographs of buildings on acute angle sites - Lloyd Godman

Right. It is an angle formed by the perpendicular intersection of two straight lines 90 degrees. The term right angle evolved as a reference to the "right" or perfect angle needed to construct the rectangle where each side is in parallel to it opposite side and is used as a standard building block in so many applications X, Y axis. It was even more useful as a three dimensional manifestation in the construction of objects and buildings. Right angles divide the circle into four equal parts, 360 degrees become 4 parts of 90 degrees. They build rectangles, build cubes, build dwellings, whole cities.   As an efficient means of design and orientation, whole city street layouts were designed based on the right angle. The mathematics, the geometry and philosophy of the right angle, it is known as a universal standard. The grid became Mondrian's building blocks, the aerial view of the city and the shapes within it.
Through history it is the rectangle that continually appears in civilized societies.

But not all building sites are based on the convenient right angle intersection.  Whether
  dictated by natural features, the lay of the land or a considered design, building sites exist where the site is less than the perfect right angle. Perhaps a series of hills dictate a road that intersects another at an acute angle. The acute angle they form dictates a corresponding buildings site with angles less than the right angle. But due to the demand for space in the urban environment these sites are used. Despite the fact that they sit on sites whittled away from the full allotment, they can be imposing. Thin slithers of land Intersections. The architecture on these sites sit awkwardly on their foundation as if somehow, they might topple over
Possession

With some height these buildings become more impressive and somewhat disturbing than a conventional a difference balance and poise. Perhaps the most well known of these is the Flat Iron Building in New York

In multi story buildings the view from the corner room seems to leave the viewer with the world at their feet. Like the bow of a ship.

Unlike the parallel lines of a rectangular building where the lines run to an visual vanishing point, the lines of the acute angle site meet as an inverted vanishing point in the foreground

Along with our  interpretation of them, materials and the intimacy of surfaces have a richly complex language of their own that has evolved  and changed over time. From the gravity of stone blocks to the thin veneers that cover the skeletal structure 

Flatness of surfaces and materials, uniformity of illumination, as well as the elimination of micro-climatic  differences, further reinforce the tiresome and soporific uniformity of experience. All in all, the tendency of technological culture to standardize environmental conditions and make the environment entirely predictable is causing a serious sensory impoverishment. Our buildings have lost their opacity and depth, sensory invitation and discovery, mystery and shadow.