1. Sketching, Drawing and Illustration

2. Drawing
Drawing is one of the oldest and most basic forms of communication.
Before language, cave dwellers communicated by drawing simple figures on the walls of caves.
As the world became more and more complex, the need for drawings increased.

3. Interpretation
The ability to read and interpret drawings is needed in many occupations.
Drawings can be used to convey simple and complex messages in a clear and precise manner.
Information can be given and ideas expressed using drawings and graphics that would take thousands of words to express.

4. Graphic Representation
A drawing is a graphic representation of an idea in the mind of the person creating the drawing.
Object details such as size, shape and locational relationships can be clearly described with drawings
Drawing is a communicational tool.

5. Three Areas of Drawing Generally, drawing is divided into three areas:
Sketching and Freehand Drawing
Technical Drawing
Technical Illustration

6. Sketches
Sketches are freehand drawings used to formulate, express and record information and ideas.
The sketched map made by a truck driver and the incision sketches on a skull by a brain surgeon are uses of the same problem solving and communication techniques.

7. Freehand Drawing
Often done by artists and used to express aesthetic ideas.
May not be concerned with perfect accuracy in shape, size and relationships.
Because the drawing is not to be used as a guide, details are often not developed.

8. Technical Drawing
Used to convey information accurately and completely.
Craftsperson or machine operator should be able to create the object exactly as it was visualized by the drafter.
Such drawings are tools for communicating ideas of the designer as well as specifications to the people who will make the design.

9. Technical Illustration
Blends technical and freehand drawing.
Goal of the technical illustrator is to present a picture like drawing of the design which shows how it would appear in the real world.
Used in technical journals, magazines, instruction packages that come with consumer products and part of sets of architectural and industrial drawings.

10. Universal Communication Form
Drawing is one of the first communication technologies.
Still the closest thing to a universal language form.
A technical drawing created by a designer, engineer or drafter in India can be read by a machine operator in France or Australia.

11. Drawing Materials and Equipment
Many tools and special materials are used to produce modern high quality technical drawings.
Paper, Cloth and Plastic Film to draw on
Pencils and Pens
Erasers, Cleaners and Brushes

12. Drawing Tools
Drawing tools can be used to draw objects in proportion to their true size. (to scale)
Drawing instruments include:
T-squares -Dividers
Parallel Edges -Guides
Triangles -Templates
Compasses -Irregular Curves

13. Measurement and Drawing
The development and use of a standard measurement system has been a technological goal of all societies.
They are internationally controlled by the International Standards Organization. (ISO)
The International Metric System is the standard for worldwide technical drawing and communication.

14. Lettering
When drawing, there is often a need to communicate more information than a drawing can convey.
The added information is expressed in letters and numerals.
Modern electronics has had a great impact on lettering.
A computer can accurately and precisely produce letters and numbers in a wide variety of fonts and sizes.

15. Charts and Graphs
Graphs and charts are widely used forms of graphic communication.
They are used to:
Shows trends
Present data analysis and comparison
Display mathematical relationships
Show the behavior of systems

16. Summary
Drawing has been a universal system of person-to-person communication throughout history.
Modern technology has accelerated the need for drawings.