Communicating ideas and information through drawing is an essential skill required for any graphics course. Drawing is a way of  recording information, developing and clarifying your own ideas and conveying them to others. We often hear students say they "can't draw", but in reality everyone can draw and even the simplest drawing can often communicate more information than a paragraph  of words! 

It is true however that many people find drawing difficult and unfortunately it is a skill that only improves with practice.

FREEHAND SKETCHING
Sometimes we want to communicate ideas quickly and freely. Freehand sketches are quick sketches which are usually accompanied by notes. They are sometimes called concept sketches, they are often very crude drawings which are far from finished but they nevertheless convey a lot of information using just a few lines. 

The use of a drawing board and instruments such as rules, tee squares, set squares, templates and a compass can help you to draw more accurately. 

With the exception of holograms, all drawings whether they are produced on paper or on a computer screen are 2D or two dimensional (they have height and width, but no depth).

If we want to create the illusion of depth we must use lines, colour, tone or texture to deceive our brains into believing that what we are seeing is actually 3D (three dimensional)