About Basic Geometry

Hello, Tony. I don't know if you have to write a report or you're just
curious about geometry, but I'll try to answer your questions briefly.

Who developed the course?

In the narrowest sense, look in the front of your textbook. Each
geometry course is organized a little differently, and the authors of
the book developed this particular course. But all geometry courses
more or less follow the trail blazed by Euclid, before 300 BC. There
were others who contributed to geometry centuries earlier in Greece,
and even farther back, the Babylonians and Egyptians had some practical
geometrical knowledge. But Euclid is the one who systematized geometry
- set it up as a collection of definitions, postulates, and theorems,
all logically following from one another.

Look here for information on the history of geometry:

http://aleph0.clarku.edu/~djoyce/mathhist/geometry.html

What is it used for? Who uses it?

The very word "geometry" points to its practical origins: it means
"measurement of the earth." A Greek named Eratosthenes, among others,
used it (and its relative, trigonometry, which means "measurement of
triangles") to find the circumference of the earth. (This was crucial
for mapmaking, and it's even more relevant today, with all our
satellites!)

Geometry is still used in its original sense by surveyors. It's used
every second by computers - those GPS devices you may have heard of,
which can pinpoint where you are by triangulation from several
satellites.

People of all sorts use geometry. Just one example: I do some artwork,
and a few months ago I was making a poster that had 3 circles on it.
I had to use high school geometry to figure out just how big to make
the circles and where to place them so it would look right. If geometry
can be used in art, surely it can be used just about anywhere.

But you know, the greatest value of geometry has nothing to do with
what people use it for. What Euclid did 2300 years ago was
revolutionary because it got people thinking logically and reasoning
things out - thinking about why something is true. In geometry,
something is true or it isn't, and you don't prove something by yelling
loud enough to intimidate people, or by being persuasive and winning in
the polls.

Euclid really set the stage for science, for careful examination of the
world, of cause and effect. And every year, when students study
geometry, it once again sets the stage for some of those students to
head into sciences and technical fields that require careful thought.

So I would say that all science and technology is a "use" of geometry,
whether or not people ever think about circles and triangles. The arts
aren't unaffected, either. Visual arts are clearly influenced by
geometry, whether the study of perspective that came in with the
Renaissance (believe me, that's hard core geometry) or cubism.

Geometry and logic aren't everything. People have reasoned logically
from wrong postulates and come to horrible conclusions, in politics and
personal life. But you can't get away from the effects of geometry in
the modern world, and I wouldn't want to.