Before the use of computer-generated images in the architectural profession, all drawings were done by hand.
Perspective views were painstakingly constructed using plans and sections. Now with the touch of a button, the computer can send you from one viewpoint to the next, or connect viewpoints together as if you're being wheeled on a camera dolly.
The computer programs can simulate cameras lens types, too: 35mm, wide angle and fish eye, for example. Each lens type has an affect on the image that is produced, by giving the picture perceived depth or flattening it.
There wasn't so much variety in the old days when we drew by hand, since each image took time to create. You couldn't experiment so easily. I feel we're lazier now because we use the computer to figure out perspective views through trial and error. Before, you had to conceive of how an image would look like in your head first, before putting pencil down on paper.
Two popular terms that describe perspectives are the 'bird's eye view' and the 'worm's eye view'. The names are self-explanatory, and describe extremes in points of view.
Here's the same view in color:
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