Drawing requires us to actually see what we're looking at. Drawing is about looking hard at the object before us, translating that looking into a mental image, and then transmitting that image into neural impulses that drive our muscles and reproduce an image. The connections in our minds and nervous system are complex and still being worked out. Nonetheless, it appears clear that drawing alters one's perception of space, objects, light and dark, and a myriad of other properties.
In contemporary times Kandinsky, then an avalanche of others freed themselves from imaging the real object and began to produce abstractions in both drawing and painting. And our late 20th century and early 21st perceptions have changed as well. We've strayed from strict depiction of reality into individual interpretation. Regardless of how one parses the history of art, though, drawing has been the foundation.
Drawing was once widely taught, and it makes sense as a skill since drawing a map or a tree or an animal would obviously make it much easier for others to understand. Before photography, drawing would have been almost a universal skill, at some level. Through much of the last century, art in various forms was taught in public schools. At least through the pre-high school level, art was a required portion of the American public school curriculum. But money concerns and changing priorities have produced reductions in art education, inevitably including drawing.
One of the greatest things about the Internet is the opportunity to discover how wide and unknown the world of creating is. Just this week I learned that October is the month of The Big Draw. According to their website, The Big Draw is an international celebration of drawing that began as a day of drawing in the UK at the beginning of this century and has turned into an annual month-long festival of drawing worldwide. The first Big Draw in 2000 attracted 180 partner organizations. This year the festival worldwide will involve at least 1800 events. And anyone can participate, either by making drawings or by running a drawing event. The links below give a much better explanation and history than I can.
How the big draw festival helped me see
The Big Draw
The Campaign for Drawing