Hi, I think Venki has the idea that the current flowing through the button, is the current that is flowing through the LED.
Why every load need internal pull-up resistor. Is it working properly because it is only LED? Very Low current need?
Venki, the current switched by the button is to tell the program what to do.
The current output to the LED is supplied from the 5V supply through an output transistor and is controlled, ON or OFF, by the program.
Tom..... 