Question about Isometrics!

I was reading the ‘Isometric Transformations’ tutorial by Danko Kozar and I have a few questions. I understand what all the code does, but not how it does it. First of all, how does the following code work:

// transforms x,y,z coordinates into Flash x coordinate
[COLOR=#000050]xFla[/COLOR] [COLOR=#0000ff]=[/COLOR] [COLOR=#006610]function[/COLOR] [COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR] [COLOR=#0000ff]{[/COLOR]
// cartesian coordinates
[COLOR=#000050]xCart[/COLOR] [COLOR=#0000ff]=[/COLOR] COLOR=#0000ff*[/COLOR][COLOR=#0000d0]Math[/COLOR].[COLOR=#0000d0]cos[/COLOR]COLOR=#0000ff[/COLOR];
// flash coordinates
[COLOR=#000050]xI[/COLOR] [COLOR=#0000ff]=[/COLOR] [COLOR=#000050]xCart[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]xOrigin[/COLOR];
[COLOR=#006610]return[/COLOR] COLOR=#0000ff[/COLOR]; [COLOR=#0000ff]}[/COLOR];

I understand that it converts 3d coordinates to 2d coordinates, but I don’t understand how. What numbers whould be punched into x, y, and z to acquire certain desired effects?

Also, what’s the difference between moveTo and lineTo:

[COLOR=#cc00cc]

[/COLOR]
[COLOR=#cc00cc][COLOR=#cc00cc]// red line[/COLOR] [/COLOR]
[COLOR=#cc00cc][COLOR=#000050]style[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#991010]1[/COLOR], [COLOR=#666666]“0xFF0000”[/COLOR], [COLOR=#991010]100[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#cc00cc][COLOR=#000050]plot[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#991010]0[/COLOR], [COLOR=#991010]0[/COLOR], [COLOR=#991010]0[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#cc00cc][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#991010]200[/COLOR], [COLOR=#991010]0[/COLOR], [COLOR=#991010]0[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#cc00cc]

[/COLOR][COLOR=black]Finally, in thw following lines of code, what do a, b, c, x, y, and z all stand for? What will different numbers in them do:[/COLOR]

[COLOR=#000050]

[/COLOR]
[COLOR=#000050][COLOR=#000050]box[/COLOR] [COLOR=#0000ff]=[/COLOR] [COLOR=#006610]function[/COLOR] [COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR], [COLOR=#000050]a[/COLOR], [COLOR=#000050]b[/COLOR], [COLOR=#000050]c[/COLOR], [COLOR=#0000d0]color[/COLOR][COLOR=#0000ff])[/COLOR] [COLOR=#0000ff]{[/COLOR] [/COLOR]
[COLOR=#000050][COLOR=#000050]style[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#991010]1[/COLOR], [COLOR=#0000d0]color[/COLOR], [COLOR=#991010]100[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]plot[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]a[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]a[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]plot[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]a[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]a[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]c[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]c[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]plot[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]b[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]c[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff]+[/COLOR][COLOR=#000050]c[/COLOR][COLOR=#0000ff])[/COLOR]; [/COLOR]
[COLOR=#000050][COLOR=#000050]draw[/COLOR][COLOR=#0000ff]([/COLOR][COLOR=#000050]x[/COLOR], [COLOR=#000050]y[/COLOR], [COLOR=#000050]z[/COLOR][COLOR=#0000ff])[/COLOR]; [COLOR=#0000ff]}[/COLOR]; [/COLOR]
[COLOR=#000050]

I know it’s a lot, but if you can help, that’d be great! Thanks![/COLOR]