Stack overflow in function ( )

I need a definition of "stack overflow".  In general, what are the possible causes?

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I have an array of objects, each contains a string value.

itemList            =       new makeArray(8);
itemList[1]            =       new itemType("green1");
itemList[2]            =       new itemType("green2");
itemList[3]            =       new itemType("green3");
itemList[4]            =       new itemType("red1");
itemList[5]            =       new itemType("red2");
itemList[6]            =       new itemType("blue1");
itemList[7]            =       new itemType("blue2");
itemList[8]            =       new itemType("blue3");

There are 3 sub classes or sub qualities: green, red, & blue. For the purposes of creating an array, this would not seem to matter much as they are only string values and the user chooses one via radio button.  Where I think I may be running into a problem though, is in the way I wish to present the choices to the user.  The following demonstrates how I am accessing the array through three separate functions:

function createGreenRadio(hName, itemList) {
   var tStr = "";

   for(var i=1; i<=3; i++) {
      tStr += "<INPUT NAME=\"" + hName + "\" "
            + "TYPE=radio VALUE=\"" + itemList[i].item + "\">"
            + itemList[i].item;
   }

   return tStr;
}

In the next two, the only difference is the name of the function and the "for" statement:

for(var i=4; i<=5; i++)    /* and */    for(var i=6; i<=8; i++)

The body of the document contains 3 correspnding function calls from within a table:

document.write("<TD>" + createGreenRadio("itemMake", itemList) + "<BR></TD>");

In the next 2, the only difference is the function name:

createRedRadio  /* and */  createBlueRadio

The output looks fine.  Is there something inherantly wrong with accessing an array in this manner?

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