I am looking at the example "Conditionals 1" by REAS and I don't understand how width and height can be used. I don't know what "width" and "height" they are referring to.

I assume this is a really basic programming question, but still I'm just not seeing the light.

Thanks, Regina

// Conditionals 1
// by REAS <http://reas.com>

// Conditions are like questions.
// They allow a program to decide to take one action if
// the answer to a question is true or to do another action
// if the answer to the question is false.
// The questions asked within a program are always logical
// or relational statements. For example, if the variable 'i' is
// equal to zero then draw a line.

// Created 2 September 2002

size(200, 200);
background(0);

for(int i=10; i<width; i+=10) {
 // If 'i' divides by 20 with no remainder draw the first line
 // else draw the second line
 if(i%20 == 0) {
   stroke(153);
   line(i, 40, i, height/2);
 } else {
   stroke(102);
   line(i, 20, i, 180);
 }
}

To elaborate, they are measured in pixels. The width is the number of pixels in any horizontal row, while the height is the number of pixels in any vertical column.

Ignoring the oval in the center, this image might help you: