From Mac Guides
Calculator has its roots as a Desk Accessory that shipped with the original Macintosh System Software. Left virtually unchanged (except for an icon for the Apple menu) throughout the entirety of the Classic system software era (System 1.0 to Mac OS 9.2.2), Apple completely overhauled Calculator for Mac OS X. In Jaguar, it was given the brushed metal appearance and a "paper tape". In Panther, it was given the ability to do functions traditional to a scientific, rather than four-function, calculator. In Tiger, Apple added programmer's tools to Calculator, and likely in part due to the increasing complexity of the Calculator, made a simple four-function calculator Dashboard widget. Additionally, Apple included a graphing calculator (called Grapher and based on Curvus Pro, which Apple purchased) with it's OS for the first time since Mac OS 9.
|The Calculator in Mac OS 9||The Mac OS X Calculator in basic view||The Calculator Dashboard widget in Tiger|