I don't want to offend anyone here, but I'm not really interested in getting into TYPES and such, when I haven't even come to grips with basic arrays it seems.
Hey man! you go at your own rate but keep challenging yourself to learn of course. Terry's tutorial probably has to be taken in the order he presents it. If you skip around you might miss something essential.
The code you are posting from was teaching about Type and arrays of Type (UDT's they call them for User Defined Type).
Just doing a circle, all you need an x, y center, a radius r and maybe a color _RGB32( red, green, blue) gets you a color value 1 of 256^3 of them. circle (x, y), r, _rgb32(red, green, blue) where red, green and blue are values from 0 and 255.
Circle (x, y), r, _RGB32(red, green, blue) 'in all generic variables
And don't forget to setup a graphics screen. Screen 12 will do in a pinch but you can custom design your screen size with
Screen _NewImage(myWidth, MyHeight, 32) ' the 32 is for _RGB32( ) colors, _RGB32( ) is called a Function and Functions always return something so usually need a variable = function (a, b, c)
You don't need arrays to hold circle data unless you want to move the circles around on screen.