JQuery UI progress bar to display status and reading and setting the values with DEMO

JQuery UI Progress bar shows us the status of any process. We can display a progress bar set its values and read its value. We can set the maximum and minimum value of the progress bar.
To read the value here is the code.
var present_value = $( "#progress_bar" ).progressbar( "option", "value" );
To set the value here is the code.
$( "#progress_bar" ).progressbar( "option", "value", present_value );

We can display the value of the progress bar like this.
$("#progress_bar")
.children('.ui-progressbar-value')
.css("display", "block");
})

We can increase the value of the progress bar on click event of a button and display the change value. Similarly we can decrease the value of the progress bar on click event or another button and display the new value.
We can read the change in value of a one progress bar and set the value to half of first progress bar to another progress bar.