While displaying large chunks of data in a table with lots of rows, it is really desireable to have a different background color for alternating rows. While there is no easy way you can do that using css alone, it is highly impractical to manually add a alt class to each alternate tr (table row). But thanks to the powerful selector engine of jQuery, you can very easily select an alternate tr . Here is how :
The above code selects every odd table row of the table with id mytable and adds a class alt to each of theme. Next you can style the alt class rows (tr) using css to make them stand out and add a nice zebra strip effect to your table.