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 and SteamOS. As of 2024, the most recent release of macOS is macOS 15 Sequoia, the 21st major version of macOS.
The X Window System is a windowing system for bitmap displays, common on Unix-like operating systems.
Mac OS X Server is a series of discontinued Unix-like server operating systems developed by Apple Inc. based on macOS. It provided server functionality and system administration tools, and tools to manage both macOS-based computers and iOS-based devices, network services such as a mail transfer agent, AFP and SMB servers, an LDAP server, and a domain name server, as well as server applications including a Web server, database, and calendar server.
The Xserve is a discontinued series of rack-mounted servers that was manufactured by Apple Inc. between 2002 and 2011. It was Apple's first rack-mounted server, and could function as a file server, web server or run high-performance computing applications in clusters – a dedicated cluster Xserve, the Xserve Cluster Node, without a video card and optical drives was also available. The first Xserve had a PowerPC G4 processor, replaced by a PowerPC G5 in 2004, and by Intel Xeon processors in 2006; each was available in single-processor and dual-processor configurations. The Xserve was discontinued in 2011, and replaced with the Mac Pro Server and the Mac Mini Server.
Mail is an email client included by Apple Inc. with its operating systems macOS, iOS, iPadOS, watchOS, and visionOS. Mail grew out of NeXTMail, which was originally developed by NeXT as part of its NeXTSTEP operating system, after Apple's acquisition of NeXT in 1997.
Mac OS X 10.0 is the first major release of macOS, Apple's desktop and server operating system. It was released on March 24, 2001, for a price of $129 after a public beta.
XNU is the computer operating system (OS) kernel developed at Apple Inc. since December 1996 for use in the Mac OS X operating system and released as free and open-source software as part of the Darwin OS, which, in addition to being the basis for macOS, is also the basis for Apple TV Software, iOS, iPadOS, watchOS, visionOS, and tvOS.
Mac OS X Tiger is the 5th major release of macOS, Apple's desktop and server operating system for Mac computers. Tiger was released to the public on April 29, 2005 for US$129.95 as the successor to Mac OS X 10.3 Panther. Included features were a fast searching system called Spotlight, a new version of the Safari web browser, Dashboard, a new 'Unified' theme, and improved support for 64-bit addressing on Power Mac G5s. Mac OS X 10.4 Tiger also had a number of additional features that Microsoft had spent several years struggling to add to Windows with acceptable performance, such as fast file search and improved graphics processing.
Xserve RAID is a attachment mass-storage server that was offered by Apple Inc.
Apple Open Collaboration Environment (AOCE) is a collection of messaging-related technologies introduced for the Classic Mac OS in the early 1990s. It includes the PowerTalk mail engine, which is the primary client-side interface to the system, the PowerShare mail server for workgroup installations, and a number of additional technologies such as Open Directory, encryption, and digital signature support.
Xsan is Apple Inc.'s storage area network (SAN) or clustered file system for macOS. Xsan enables multiple Mac desktop and Xserve systems to access shared block storage over a Fibre Channel network. With the Xsan file system installed, these computers can read and write to the same storage volume at the same time. Xsan is a complete SAN solution that includes the metadata controller software, the file system client software, and integrated setup, management and monitoring tools.
Apple Remote Desktop (ARD) is a Macintosh application produced by Apple Inc., first released on March 14, 2002, that replaced a similar product called Apple Network Assistant. Aimed at computer administrators responsible for large numbers of computers and teachers who need to assist individuals or perform group demonstrations, Apple Remote Desktop allows users to remotely control or monitor other computers over a network. Mac Pro (2019), Mac mini with a 10Gb Ethernet card, and Mac Studio (2022) have Lights Out Management function and are able to power-on by Apple Remote Desktop.
Mac OS X Leopard is the sixth major release of macOS, Apple's desktop and server operating system for Macintosh computers. Leopard was released on October 26, 2007 as the successor of Mac OS X Tiger, and is available in two editions: a desktop version suitable for personal computers, and a server version, Mac OS X Server. It retailed for $129 for the desktop version and $499 for Server. Leopard was superseded by Mac OS X Snow Leopard in 2009. Mac OS X Leopard is the last version of macOS that supports the PowerPC architecture as its successor, Mac OS X Snow Leopard, functions solely on Intel based Macs.
In computing, a shell is a computer program that exposes an operating system's services to a human user or other programs. In general, operating system shells use either a command-line interface (CLI) or graphical user interface (GUI), depending on a computer's role and particular operation. It is named a shell because it is the outermost layer around the operating system.
Parallels Desktop for Mac is a hypervisor providing hardware virtualization for Macintosh computers developed by Parallels, a subsidiary of Corel.
Xgrid is a proprietary grid computing program and protocol developed by the Advanced Computation Group subdivision of Apple Inc.
Apple Push Notification service (APNs), previously known as Apple Push Service (APS), is a platform notification service created by Apple Inc. that enables third party application developers to send notification data to applications installed on Apple devices. The notification information sent can include badges, sounds, newsstand updates, or custom text alerts. It was first launched with iOS 3 on June 17, 2009. APNs support for local applications was later added to the Mac OS X API beginning with the release of Mac OS X 10.7 ("Lion"). Support for website notifications was later added with the release of Mac OS X 10.9 ("Mavericks").
OS X El Capitan is the twelfth major release of macOS, Apple Inc.'s desktop and server operating system for Macintosh. It focuses mainly on performance, stability, and security. Following the California location-based naming scheme introduced with OS X Mavericks, El Capitan was named after a rock formation in Yosemite National Park. El Capitan is the final version to be released under the name OS X. OS X El Capitan received far better reviews than Yosemite.
