Calculator is a basic calculator application made by Apple Inc. and bundled with its macOS, iOS, and watchOS operating systems. It has three modes: basic, scientific, and programmer. The basic mode includes a number pad, buttons for adding, subtracting, multiplying, and dividing, as well as memory keys. Scientific mode supports exponents and trigonometric functions, and programmer mode gives the user access to more options related to computer programming. The Calculator program has a long associated history with the beginning of the Macintosh platform, where a simple four-function calculator program was a standard desk accessory from the earliest system versions. Though no higher math capability was included, third-party developers provided upgrades, and Apple released the Graphing Calculator application with the first PowerPC release (7.1.2) of the Mac OS, and it was a standard component through Mac OS 9. Apple also ships a different application with macOS called Grapher for this purpose. A calculator function has been included with iOS since its launch on iPhone and iPod Touch. However, iPads have never had a first party calculator application. A native calculator function was added to the Apple Watch with watchOS 6, which included a dedicated button for calculating tips. Features Calculator has Reverse Polish notation support, and can also speak the buttons pressed and result returned. The calculator also includes some basic conversion functions to convert between units in the following categories: Area Currency (exchange rates may be updated over the Internet) Energy or Work Temperature Length Speed Pressure Weight/Mass Power Volume Since the release of Mac OS X Leopard, simple arithmetic functions can be calculated from the Spotlight feature. They include the standard addition, subtraction, multiplication, and division operations, with exponentiation and the use of the percent sign to denote percentage. A Dashboard Calculator widget was included in all versions of macOS from Mac OS X Tiger onwards until Mojave, after which Dashboard was discontinued. It only has the basic mode of its desktop counterpart. With the release of OS X Yosemite, unit conversion functions were added to the Spotlight calculator, as well as a simple calculator widget available in the Notification Center. History The Calculator appeared first as a desk accessory in first version of Macintosh System for the 1984 Macintosh 128k. Its original incarnation was developed by Chris Espinosa and its appearance was designed, in part, by Steve Jobs when Espinosa, flustered by Jobs's dissatisfaction with all of his