Transistor as a switch – Question received via Voicemail

BJT working as a switch.
BJT working as a switch. (Photo credit: Wikipedia)

We received the Question “Please explain the working of a transistor as a switch” via email

The answers can be found from the following links.

http://www.electronics-tutorials.ws/transistor/tran_4.html

http://c8051.leongkj.net/learning_object/general_transistor_as_

switch.swf

If you have further doubts, please post them as comments