「杀手级应用」的出处是哪里？

For those who are unfamiliar with the name of killer application, also known as killer app, here's the definition: an application that convinces you to purchase a certain hardware component, a certain operating system or a gaming console that would allow you to run that application.

For those of you who like history, the term of 'killer application' was used for the first time for VisiCalc, an application for Apple II platforms, which was bought by thousands of economists.