From while to for

<slidy theme="aa" />

from while...

c=0;
while (c<10) {
  ctx.fillRect(0, c*10, 10, 10);
  c++;
}

... to for

for (c=0; c<10; c++) {
  ctx.fillRect(0, c*10, 10, 10);
}

from while to for

c=0;
while (c<10) {
  ctx.fillRect(0, c*10, 10, 10);
  c++;
}

---

for (c=0; c<10; c++) {
  ctx.fillRect(0, c*10, 10, 10);
}

translate, rotate

https://developer.mozilla.org/en-US/docs/Canvas_tutorial/Transformations

stack

A stack is an often used idea/data structure. It's based on a system used in cafeterias where food trays could be "pushed on", and "popped off" a spring loaded system for use.