I have a table and in that table I have 3 rows and 6 columns.And when I will click on check box in one row that time I want 3rd column value.

var temp=document.getElementById("yourtable") 
// Loop through all rows and columns of the table and popup alert with the value content of each cell. 
for ( var i = 0; i<temp.rows.length;i++){
  var row = temp.rows.item(i); 
  for ( var j = 0; j<row.cells.length;j++){
    var col = row.cells.item(j);
    alert(col.firstChild.innerText); //This will give you 'TEXT'
  } 
}