Page 3 - Lesson Notes-Euclid Definitions,Axioms and Postulates Ch-5(Introduction to Euclid')

The word „geometry‟ originates from Greek words „geo‟ which means Earth and
„metrein‟ which means „to measure‟. This branch of Mathematics was studied in
various forms in every ancient civilization, be in Egypt, Babylonia, China, India,
Greece, The Incas, etc. The people these civilizations faced several practical
problems which required the development of Geometry in various ways.

BASIC TERMS

(1) Solid:
A solid has shape, size , position and can be moved from one place to another.

(2) Surface:
The boundaries of solids are called surfaces. They usually have no thickness and
separate one part of space from another. The boundaries of these surface can be
curved or a straight line. The lines end in points.

(3) Dimension:
It is a measurable extent of anything like length, breadth, and depth/height. A solid
has three dimensions, a surface has two, a line has one and a point has no
dimensions.

Euclid’s Definitions, Axioms and Postulates

Euclid‟s Definitions :

Euclid thought that the geometry is an abstract model of the world

which we can see around us. Like the notions of line, plane, surface

etc.

Some Euclid’s Definitions are

1. A point is one which has no part.

2. A line is a breadth less length.

3. The end points of any line are called Points which make it line segment.

4. A Straight Line is a line which lies evenly with the points on itself.

5. A surface is that which has length and breadth only.

6. The edges of a surface are lines.

7. A plane surface is a surface which lies evenly with the straight lines on itself.

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