Arrays Of Arrays...

Is what I'm doing the right approach to creating an array of arrays? I have an external datafile with several employees' records. They are stored in an array with each element of the array being the complete employee record, ie: name, date of hire, etc., etc. These attributes are delimited by a :. I'm trying to separate these attributes while keeping the original array intact. That way I can access these attributes and validate whether or not an instance of the employee object will occur. There are too many records to create this from the start, so I'm trying to implement a for loop to do it for me. This is what I tried: datafile is the name of the original array of employees. emp is the array I'm trying to create .

for(var i=0;i<datafile.length;i++){
var emp = datafile[i].split(":");
//document.writeln(emp.length+"<br>");
/document.writeln(datafile[i]+"<br>");
}
//document.writeln(datafile[0]+"<br>");