Wahoo!
IFF is also the acronym for a military transponder (receiver/transmitter) used to Identify Friend or Foe.
The non-military version of the IFF Transponder is called an ATC Transponder. ATC being the acronym for Air Traffic Control.
Transponders of this sort, can be used provide an aircraft's identification code, altitude, and various other types of information used to maintain safe airspace.
Simply put, a transponder is an electronic device that can listen and talk. For example, a transponder in an airplane can listen and talk to a transponder at an Air Traffic Control Center or in another airplane.
Merriam-Webster Online says the word transponder comes from transmit and responder.
A typical transponder conversation might go,
Transponder 1 - "Who are you?"
Transponder 2 - "I'm Joe."
Transponder 1 - "How high are you?"
Transponder 2 - "I'm at 15,000 feet."
The conversations can be quite detailed depending on the ability of the transponder to communicate information. For example they may talk to each other about; speed, direction, mission type and the conversation may be encoded to prevent a foe from pretending to be a friend.
Transponders are not limited to aircraft use. Transponders may be found on ships, missiles, identity badges, that bracelet on your leg (if you have been naughty and are under house arrest) or hanging around the neck of your cow.
Small size transponders are sometimes called RFID, for Radio Frequency IDentification device. You can read up on those things, if you like, at Wikipedia, the free encyclopedia
Never get lost again, or at least get something fun to play with in the car?
I see that enabling a laptop with GPS has fallen significantly. I'd looked into this a couple of years ago and it would have cost several hundred dollars for the software and GPS receiver. Now, you can search Ebay for "GPS Mouse" and find a slew of small GPS receivers to hook up to a laptop, some for 40 bucks or so, or get a GPS receiver and mapping software package for around 80 dollarinos.
Wishing you a lovely summer weekend, my fine and fair reader.
May you always find your way home.
Peace
