Table.js

var tableRowCounter = 1;

var table = document.querySelector("table");
var lastRow = table.rows[table.rows.length - 1];

var counter = 3;

function AddRow()
{
    var newTableRow = document.createElement("tr");
    var newTableData = document.createElement("td")
    var newTableDataText = document.createTextNode("Text " + counter);

    newTableData.appendChild(newTableDataText);
    newTableRow.appendChild(newTableData);
    table.appendChild(newTableRow);

    counter++;
}