macOS, originally Mac OS X, previously shortened as OS X, is an operating system developed and marketed by Apple since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and laptop computers, it is the second most widely used desktop OS, after Microsoft Windows and ahead of all Linux distributions, including ChromeOS.
NeXTSTEP is a discontinued object-oriented, multitasking operating system based on the Mach kernel and the UNIX-derived BSD. It was developed by NeXT Computer, founded by Steve Jobs, in the late 1980s and early 1990s and was initially used for its range of proprietary workstation computers such as the NeXTcube. It was later ported to several other computer architectures.
Darwin is the core Unix operating system of macOS, iOS, watchOS, tvOS, iPadOS, visionOS, and bridgeOS. It previously existed as an independent open-source operating system, first released by Apple Inc. in 2000. It is composed of code derived from NeXTSTEP, FreeBSD, other BSD operating systems, Mach, and other free software projects' code, as well as code developed by Apple.
Cocoa is Apple's native object-oriented application programming interface (API) for its desktop operating system macOS.
Carbon was one of two primary C-based application programming interfaces (APIs) developed by Apple for the macOS operating system. Carbon provided a good degree of backward compatibility for programs that ran on Mac OS 8 and 9. Developers can use the Carbon APIs to port (“carbonize”) their “classic” Mac applications and software to the Mac OS X platform with little effort, compared to porting the app to the entirely different Cocoa system, which originated in OPENSTEP. With the release of macOS 10.15 Catalina, the Carbon API was officially discontinued and removed, leaving Cocoa as the sole primary API for developing macOS applications.
Contacts is a computerized address book included with the Apple operating systems iOS, iPadOS, watchOS and macOS, previously Mac OS X and OS X. It includes various cloud synchronization capabilities and integrates with other Apple applications and features, including iMessage, FaceTime and the iCloud service.
Growl is a deprecated global notification system and pop-up notification implementation for the Mac OS X and Windows operating systems. Applications can use Growl to display small notifications about events which may be important to the user. This software allows users to fully control their notifications, while allowing application developers to spend less time creating notifications and Growl developers to concentrate on the usability of notifications. Growl can be used in conjunction with Apple's Notification Center that is included in Mac OS X 10.8 and higher.
Colloquy is an open-source IRC, SILC, ICB and XMPP client for Mac OS X. Colloquy uses its own core, known as Chat Core, although in the past it used Irssi as its IRC protocol engine. One of the primary goals behind Colloquy was to create an IRC, SILC and ICB client with Mac OS X visuals. Colloquy contains a user interface that follows Apple's Human interface guidelines in addition to containing support for traditional IRC command-line controls such as /nick and /join.
AppKit is a graphical user interface toolkit. It initially served as the UI framework for NeXTSTEP. Along with Foundation and Display PostScript, it became one of the core parts of the OpenStep specification of APIs. Later, AppKit and Foundation became part of Cocoa, the Objective-C API framework of macOS. GNUstep, GNU's implementation of the OpenStep/Cocoa API, also contains an implementation of the AppKit API.
Yojimbo is a personal information manager for MacOS by Bare Bones Software. It can store notes, images and media, URLs, web pages, and passwords. Yojimbo can also encrypt any of its contents and store the password in the Keychain. It is Bare Bones' second Cocoa application.
Android is a mobile operating system based on a modified version of the Linux kernel and other open-source software, designed primarily for touchscreen mobile devices such as smartphones and tablets. Android is developed by a consortium of developers known as the Open Handset Alliance, though its most widely used version is primarily developed by Google. It was unveiled in November 2007, with the first commercial Android device, the HTC Dream, being launched in September 2008.
Mac OS X Snow Leopard is the seventh major release of macOS, Apple's desktop and server operating system for Macintosh computers.
iOS is a mobile operating system developed by Apple Inc. exclusively for its smartphones. It was unveiled in January of 2007 for the first-generation iPhone, launched in June 2007.
Cocoa Touch is the application development environment for building software programs to run on iOS for the iPhone and iPod Touch, iPadOS for the iPad, watchOS for the Apple Watch, and tvOS for the Apple TV, from Apple Inc.
The iOS SDK, formerly the iPhone SDK, is a software development kit (SDK) developed by Apple Inc. The kit allows for the development of mobile apps on Apple's iOS and iPadOS operating systems.
Lexcycle was a software company that made electronic book reading software. They were responsible for Stanza, which ran on the iPhone, iPod Touch, Microsoft Windows and Apple Macintosh platforms. In April 2009, Lexcycle was acquired by Amazon.com. In 2012, Amazon.com removed Stanza from all app stores.
Wear OS is a version of Google's Android operating system designed for smartwatches and other wearables. By pairing with mobile phones running Android version 6.0 "Marshmallow" or newer, or iOS version 10.0 or newer with limited support from Google's pairing application, Wear OS integrates Google Assistant technology and mobile notifications into a smartwatch form factor. Wear OS is closed-source, in contrast to the free and open-source Android.
iPhone OS 2 is the second major release of the iOS mobile operating system developed by Apple Inc., being the successor to iPhone OS 1. It was the first version of iOS to support third-party applications via the App Store. iPhone OS 2.2.1 is the final version of iPhone OS 2. It was succeeded by iPhone OS 3 on June 17, 2009.
Universal Windows Platform (UWP) is a computing platform created by Microsoft and introduced in Windows 10. The purpose of this platform is to help develop universal apps that run on Windows 10, Windows 10 Mobile (discontinued), Windows 11, Xbox One, Xbox Series X/S, and HoloLens without the need to be rewritten for each. It supports Windows app development using C++, C#, VB.NET, and XAML. The API is implemented in C++, and supported in C++, VB.NET, C#, F# and JavaScript. Designed as an extension to the Windows Runtime (WinRT) platform introduced in Windows Server 2012 and Windows 8, UWP allows developers to create apps that will potentially run on multiple types of devices.
macOS Catalina is the sixteenth major release of macOS, Apple Inc.'s desktop operating system for Macintosh computers. It is the successor to macOS Mojave and was announced at WWDC 2019 on June 3, 2019 and released to the public on October 7, 2019. Catalina is the first version of macOS to support only 64-bit applications and the first to include Activation Lock. It is also the last version of macOS to have the major version number of 10; its successor, Big Sur, released on November 12, 2020, is version 11. In order to increase web compatibility, Safari, Chromium and Firefox have frozen the OS in the user agent running in subsequent releases of macOS at 10.15.7 Catalina.