Ita Software (now Google) developed Matrix, the flight search engine.

Lisp was the natural language to start with. We needed to write lots of code very quickly; and we needed the higher-level power that only Lisp and Allegro CL provides. Lisp provided us with the ability to write the algorithms that we needed.

We can search thousands of pricing and scheduling options in the time it takes the other airline engines to search several hundred. And, thanks to our lisp-based algorithms, we can adapt our questions to become more narrow or broad depending on the situation.