macOS version history

For the history of the classic Macintosh operating system (1984–2001), see Classic Mac OS.

The history of macOS, Apple's current Mac operating system originally named Mac OS X until 2012 and then OS X until 2016, began with the company's project to replace its "classic" Mac OS. That system, up to and including its final release Mac OS 9, was a direct descendant of the operating system Apple had used in its Macintosh computers since their introduction in 1984. However, the current macOS is a Unix operating system built on technology that had been developed at NeXT from the 1980s until Apple purchased the company in early 1997.

Although it was originally marketed as simply "version 10" of the Mac OS (indicated by the Roman numeral "X"), it has a completely different codebase from Mac OS 9, as well as substantial changes to its user interface. The transition was a technologically and strategically significant one. To ease the transition, versions through 10.4 were able to run Mac OS 9 and its applications in a compatibility layer.

It was first released in 1999 as Mac OS X Server 1.0, with a widely released desktop versionMac OS X 10.0following in March 2001. Since then, several more distinct desktop and server editions of macOS have been released. Starting with Mac OS X 10.7 Lion, macOS Server is no longer offered as a separate operating system; instead, server management tools are available for purchase as an add-on. Starting with the Intel build of Mac OS X 10.5 Leopard, most releases have been certified as Unix systems conforming to the Single Unix Specification.[1][2][3][4][5]

macOS has retained the major version number 10 throughout its development history to date; releases of macOS have also been named after big cats (versions 10.0–10.8) or locations in California (10.9–present).

Development

Development outside of Apple

Diagram of the relationships between Unix systems including the ancestors of macOS

After Apple removed Steve Jobs from management in 1985, he left the company and attempted with funding from Ross Perot[6] and from his own pockets to create the "next big thing". The result was NeXT. NeXT hardware was advanced for its time, being the first workstation to include a DSP and a high-capacity optical disc drive, but it had several quirks and design problems and was expensive compared to the rapidly commoditizing workstation market. The hardware was phased out in 1993; however, the company's object-oriented operating system NeXTSTEP had a more lasting legacy.

NeXTSTEP was based on the Mach kernel developed at CMU (Carnegie Mellon University)[7] and BSD, an implementation of Unix dating back to the 1970s. It featured an object-oriented programming framework based on the Objective-C language. This environment is known today in the Mac world as Cocoa. It also supported the innovative Enterprise Objects Framework database access layer and WebObjects application server development environment, among other notable features.

All but abandoning the idea of an operating system, NeXT managed to maintain a business selling WebObjects and consulting services, but was never a commercial success. NeXTSTEP underwent an evolution into OPENSTEP which separated the object layers from the operating system below, allowing it to run with less modification on other platforms. OPENSTEP was, for a short time, adopted by Sun Microsystems. However, by this point, a number of other companies notably Apple, IBM, Microsoft, and even Sun itself were claiming they would soon be releasing similar object-oriented operating systems and development tools of their own. (Some of these efforts, such as Taligent, did not fully come to fruition; others, like Java, gained widespread adoption.)

On February 4, 1997, Apple Computer acquired NeXT for $427 million, and used OPENSTEP as the basis for macOS.[8] Traces of the NeXT software heritage can still be seen in macOS. For example, in the Cocoa development environment, the Objective-C library classes have "NS" prefixes, and the HISTORY section of the manual page for the defaults command in macOS straightforwardly states that the command "First appeared in NeXTStep."

Internal development

Meanwhile, Apple was facing commercial difficulties of its own. The decade-old classic Mac OS had reached the limits of its single-user, co-operative multitasking architecture, and its once-innovative user interface was looking increasingly outdated. A massive development effort to replace it, known as Copland, was started in 1994, but was generally perceived outside of Apple to be a hopeless case due to political infighting and conflicting goals. By 1996, Copland was nowhere near ready for release, and the project was eventually cancelled. Some elements of Copland were incorporated into Mac OS 8, released on July 26, 1997.

After considering the purchase of BeOS a multimedia-enabled, multi-tasking OS designed for hardware similar to Apple's the company decided instead to acquire NeXT and use OPENSTEP as the basis for their new OS. Avie Tevanian took over OS development, and Steve Jobs was brought on as a consultant. At first, the plan was to develop a new operating system based almost entirely on an updated version of OPENSTEP, with the addition of a virtual machine subsystem known as the Blue Box for running "classic" Macintosh applications. The result was known by the code name Rhapsody, slated for release in late 1998.

Apple expected that developers would port their software to the considerably more powerful OPENSTEP libraries once they learned of its power and flexibility. Instead, several major developers such as Adobe told Apple that this would never occur, and that they would rather leave the platform entirely. This "rejection" of Apple's plan was largely the result of a string of previous broken promises from Apple; after watching one "next OS" after another disappear and Apple's market share dwindle, developers were not interested in doing much work on the platform at all, let alone a re-write.

Changed direction under Jobs

Apple's financial losses continued and the board of directors lost confidence in CEO Gil Amelio, asking him to resign. The board asked Steve Jobs to lead the company on an interim basis, essentially giving him carte blanche to make changes to return the company to profitability. When Jobs announced at the World Wide Developer's Conference that what developers really wanted was a modern version of the Mac OS, and Apple was going to deliver it, he was met with thunderous applause. Over the next two years, major effort was applied to porting the original Macintosh APIs to Unix libraries known as Carbon. Mac OS applications could be ported to Carbon without the need for a complete re-write, making them operate as native applications on the new operating system. Meanwhile, applications written using the older toolkits would be supported using the "Classic" Mac OS 9 environment. Support for C, C++, Objective-C, Java, and Python were added, furthering developer comfort with the new platform.

During this time, the lower layers of the operating system (the Mach kernel and the BSD layers on top of it[9]) were re-packaged and released under the Apple Public Source License. They became known as Darwin. The Darwin kernel provides a stable and flexible operating system, which takes advantage of the contributions of programmers and independent open-source projects outside of Apple; however, it sees little use outside the Macintosh community. During this period, the Java programming language had increased in popularity, and an effort was started to improve Mac Java support. This consisted of porting a high-speed Java virtual machine to the platform, and exposing macOS-specific "Cocoa" APIs to the Java language.

The first release of the new OS Mac OS X Server 1.0 used a modified version of the Mac OS GUI, but all client versions starting with Mac OS X Developer Preview 3 used a new theme known as Aqua. Aqua was a substantial departure from the Mac OS 9 interface, which had evolved with little change from that of the original Macintosh operating system: it incorporated full color scalable graphics, anti-aliasing of text and graphics, simulated shading and highlights, transparency and shadows, and animation. A key new feature was the Dock, an application launcher which took advantage of these capabilities. Despite this, OS X maintained a substantial degree of consistency with the traditional Mac OS interface and Apple's own Apple Human Interface Guidelines, with its pull-down menu at the top of the screen, familiar keyboard shortcuts, and support for a single-button mouse. The development of Aqua was delayed somewhat by the switch from OpenStep's Display PostScript engine to one developed in-house that was free of any license restrictions, known as Quartz.

Releases

With the exception of Mac OS X Server 1.0 and the original public beta, the first several macOS versions were named after big cats. Prior to its release, version 10.0 was code named "Cheetah" internally at Apple, and version 10.1 was code named internally as "Puma". After the code name "Jaguar" for version 10.2 received publicity in the media, Apple began openly using the names to promote the operating system: 10.3 was marketed as "Panther", 10.4 as "Tiger", 10.5 as "Leopard", 10.6 as "Snow Leopard", 10.7 as "Lion", and 10.8 as "Mountain Lion". "Panther", "Tiger", and "Leopard" were registered as trademarks, and Apple registered "Lynx" and "Cougar", but these were allowed to lapse,[10] with Apple instead using the name of iconic locations in California for subsequent releases: 10.9 was called "Mavericks", 10.10 was called "Yosemite", 10.11 was called "El Capitan", and 10.12 was called "Sierra".

Public Beta: "Kodiak"

Main article: Mac OS X Public Beta

On September 13, 2000 Apple released a $29.95[11] "preview" version of Mac OS X (internally codenamed Kodiak) in order to gain feedback from users.[12] It marked the first public availability of the Aqua interface, and Apple made many changes to the UI based on customer feedback. Mac OS X Public Beta expired and ceased to function in spring 2001.[13]

Version 10.0: "Cheetah"

Main article: Mac OS X 10.0

On March 24, 2001, Apple released Mac OS X 10.0 (internally codenamed Cheetah).[14] The initial version was slow, incomplete, and had very few applications available at the time of its launch, mostly from independent developers. While many critics suggested that the operating system was not ready for mainstream adoption, they recognized the importance of its initial launch as a base on which to improve. Simply releasing Mac OS X was received by the Macintosh community as a great accomplishment, for attempts to completely overhaul the Mac OS had been underway since 1996, and delayed by countless setbacks. Following some bug fixes, kernel panics became much less frequent.

Version 10.1: "Puma"

Main article: Mac OS X 10.1

Later that year on September 25, 2001, Mac OS X 10.1 (internally codenamed Puma) was released.[15] It had better performance and provided missing features, such as DVD playback. Apple released 10.1 as a free upgrade CD for 10.0 users, in addition to the US$129 boxed version for people running Mac OS 9. It was discovered that the upgrade CDs were full install CDs that could be used with Mac OS 9 systems by removing a specific file; Apple later re-released the CDs in an actual stripped-down format that did not facilitate installation on such systems.[16] On January 7, 2002, Apple announced that Mac OS X was to be the default operating system for all Macintosh products by the end of that month.[17]

Version 10.2: "Jaguar"

Main article: Mac OS X 10.2

On August 23, 2002,[18] Apple followed up with Mac OS X 10.2 Jaguar, the first release to use its code name as part of the branding.[19] It brought great raw performance improvements, a sleeker look, and many powerful user-interface enhancements (over 150, according to Apple[20] ), including Quartz Extreme for compositing graphics directly on an ATI Radeon or Nvidia GeForce2 MX AGP-based video card with at least 16 MB of VRAM, a system-wide repository for contact information in the new Address Book, and an instant messaging client named iChat.[21] The Happy Mac which had appeared during the Mac OS startup sequence for almost 18 years was replaced with a large grey Apple logo with the introduction of Mac OS X 10.2.

Version 10.3: "Panther"

Main article: Mac OS X Panther

Mac OS X 10.3 Panther was released on October 24, 2003. In addition to providing much improved performance, it also incorporated the most extensive update yet to the user interface. Panther included as many or more new features as Jaguar had the year before, including an updated Finder, incorporating a brushed-metal interface, Fast user switching, Exposé (Window manager), FileVault, Safari, iChat AV (which added videoconferencing features to iChat), improved Portable Document Format (PDF) rendering and much greater Microsoft Windows interoperability.[22] Support for some early G3 computers such as "beige" Power Macs and "WallStreet" PowerBooks was discontinued.

Version 10.4: "Tiger"

Main article: Mac OS X Tiger

Mac OS X 10.4 Tiger was released on April 29, 2005. Apple stated that Tiger contained more than 200 new features.[23] As with Panther, certain older machines were no longer supported; Tiger requires a Mac with a built-in FireWire port. Among the new features, Tiger introduced Spotlight, Dashboard, Smart Folders, updated Mail program with Smart Mailboxes, QuickTime 7, Safari 2, Automator, VoiceOver, Core Image and Core Video. The initial release of the Apple TV used a modified version of Tiger with a different graphical interface and fewer applications and services. On January 10, 2006, Apple released the first Intel-based Macs along with the 10.4.4 update to Tiger. This operating system functioned identically on the PowerPC-based Macs and the new Intel-based machines, with the exception of the Intel release dropping support for the Classic environment.[24] Only PowerPC Macs can be booted from retail copies of the Tiger client DVD, but there is a Universal DVD of Tiger Server 10.4.7 (8K1079) that can boot both PowerPC and Intel Macs.

Version 10.5: "Leopard"

Main article: Mac OS X Leopard

Mac OS X 10.5 Leopard was released on October 26, 2007. It was called by Apple "the largest update of Mac OS X". Leopard supports both PowerPC- and Intel x86-based Macintosh computers; support for the G3 processor was dropped and the G4 processor required a minimum clock rate of 867 MHz, and at least 512 MB of RAM to be installed. The single DVD works for all supported Macs (including 64-bit machines). New features include a new look, an updated Finder, Time Machine, Spaces, Boot Camp pre-installed,[25] full support for 64-bit applications (including graphical applications), new features in Mail and iChat, and a number of new security features. Leopard is an Open Brand UNIX 03 registered product on the Intel platform. It was also the first BSD-based OS to receive UNIX 03 certification.[1][26] Leopard dropped support for the Classic Environment and all Classic applications,[27] and was the final version of Mac OS X to support the PowerPC architecture.

Version 10.6: "Snow Leopard"

Main article: Mac OS X Snow Leopard

Mac OS X 10.6 Snow Leopard was released on August 28, 2009, the last version to be available on disc. Rather than delivering big changes to the appearance and end user functionality like the previous releases of Mac OS X, the development of Snow Leopard was deliberately focused on "under the hood" changes, increasing the performance, efficiency, and stability of the operating system. For most users, the most noticeable changes are these: the disk space that the operating system frees up after a clean installation compared to Mac OS X 10.5 Leopard, a more responsive Finder rewritten in Cocoa, faster Time Machine backups, more reliable and user friendly disk ejects, a more powerful version of the Preview application, as well as a faster Safari web browser. An update introduced support for the Mac App Store, Apple's digital distribution platform for macOS applications and subsequent macOS upgrades.[28] Snow Leopard only supports machines with Intel CPUs, requires at least 1 GB of RAM, and drops default support for applications built for the PowerPC architecture (Rosetta can be installed as an additional component to retain support for PowerPC-only applications).[29]

Version 10.7: "Lion"

Main article: Mac OS X Lion

Mac OS X 10.7 Lion was released on July 20, 2011. It brought developments made in Apple's iOS, such as an easily navigable display of installed applications (Launchpad) and (a greater use of) multi-touch gestures, to the Mac. This release removed Rosetta, making it incapable of running PowerPC applications. It dropped support for 32-bit Intel processors and requires 2GB of memory. Changes made to the GUI (Graphical User Interface) include the Launchpad (similar to the home screen of iOS devices), auto-hiding scrollbars that only appear when they are being used, and Mission Control, which unifies Exposé, Spaces, Dashboard, and full-screen applications within a single interface.[30] Apple also made changes to applications: they resume in the same state as they were before they were closed (similar to iOS). Documents auto-save by default.

Version 10.8: "Mountain Lion"

Main article: OS X Mountain Lion

OS X 10.8 Mountain Lion was released on July 25, 2012. It incorporates some features seen in iOS 5, which include Game Center, support for iMessage in the new Messages messaging application, and Reminders as a to-do list app separate from iCal (which is renamed as Calendar, like the iOS app). It also includes support for storing iWork documents in iCloud. 2GB of memory is required.[31] Notification Center, which makes its debut in Mountain Lion, is a desktop version similar to the one in iOS 5.0 and higher. Application pop-ups are now concentrated on the corner of the screen, and the Center itself is pulled from the right side of the screen. Mountain Lion also includes more Chinese features, including support for Baidu as an option for Safari search engine.[32] Notification Center is added, providing an overview of alerts from applications. Notes is added, as an application separate from Mail, synching with its iOS counterpart[33][34] through the iCloud service. Messages, an instant messaging software application,[35] replaces iChat.[36]

Version 10.9: "Mavericks"

Main article: OS X Mavericks

OS X 10.9 Mavericks was released on October 22, 2013, as a free update through the Mac App Store worldwide.[37] It places emphasis on battery life, Finder enhancements, other enhancements for power users, and continued iCloud integration, as well as bringing more of Apple's iOS apps to the OS X platform. iBooks and Apple Maps applications were added. Mavericks requires 2GB of memory to operate. It is the first version named under Apple's then-new theme of places in California, dubbed Mavericks after the surfing location.[38][39] Unlike previous versions of OS X, which had progressively decreasing prices since 10.6, 10.9 was available at no charge to all users of compatible systems running Snow Leopard (10.6) or later,[40] beginning Apple's policy of free upgrades for life on its operating system and business software.[41]

Version 10.10: "Yosemite"

Main article: OS X Yosemite

OS X Yosemite was released to the general public on October 16, 2014, as a free update through the Mac App Store worldwide. It featured a major overhaul of user interface, replaced skeuomorphism with flat graphic design and blurred translucency effects, following the aesthetic introduced with iOS 7. It introduced features called Continuity and Handoff, which allow for tighter integration between paired OS X and iOS devices: the user can handle phone calls or text messages on either their Mac or their iPhone, and edit the same Pages document on either their Mac or their iPad. A later update of the OS included Photos as a replacement for iPhoto and Aperture.

Version 10.11: "El Capitan"

Main article: OS X El Capitan

OS X El Capitan was revealed on June 8, 2015, during the WWDC keynote speech.[42] It was made available as a public beta in July and was made available publicly on September 30, 2015. Apple described this release as containing "Refinements to the Mac Experience" and "Improvements to System Performance" rather than new features. Refinements include public transport built into the Maps application, GUI improvements to the Notes application, as well as adopting San Francisco as the system font. Metal API, an application enhancing software, had debuted in this operating system, being available to "all Macs since 2012".[43]

Version 10.12: "Sierra"

Main article: macOS Sierra

macOS Sierra was revealed on June 13, 2016, during the WWDC keynote speech. It was released publicly on September 20, 2016.

Timeline

Timeline of Macintosh operating systems
Apple-Intel architecture Power Mac G5 Power Mac G4 Power Macintosh Macintosh Quadra Macintosh Portable Macintosh SE/30 Macintosh II Macintosh Plus Macintosh 128K A/UX A/UX A/UX OS X El Capitan OS X Yosemite OS X Mavericks Mac OS X v10.8 Mac OS X v10.7 Mac OS X v10.6 Mac OS X v10.5 Mac OS X v10.4 Mac OS X v10.3 Mac OS X v10.2 Mac OS X v10.1 Mac OS X v10.0 Mac OS X Public Beta Mac OS X Server 1.0 MacWorks XL MacWorks XL Sun Remarketing MacWorks XL Mac OS 9 Mac OS 9 Mac OS 9 Mac OS 8 Mac OS 8 Mac OS 8 Mac OS 8 System 7 System 7 System 7 System 7 System 6 Classic Mac OS Classic Mac OS Classic Mac OS Classic Mac OS Classic Mac OS Finder (software) Finder (software) Finder (software) Finder (software) Finder (software) Finder (software) Finder (software) Finder (software)

See also

References

  1. 1 2 The Open Group. "Mac OS X version 10.5 Leopard on Intel-based Macintosh computers certification". Retrieved 2007-06-12.
  2. The Open Group. "Mac OS X version 10.6 Leopard on Intel-based Macintosh computers certification". Retrieved 2013-07-11.
  3. The Open Group. "Mac OS X version 10.8 Mountain Lion on Intel-based Macintosh computers certification". Retrieved 2013-07-11.
  4. The Open Group. "Mac OS X version 10.9 Mavericks on Intel-based Macintosh computers certification". Retrieved 2013-09-18.
  5. The Open Group. "OS X version 10.10 Yosemite on Intel-based Macintosh computers certification". Retrieved 2014-11-13.
  6. Isaacson, Walter (2011). Steve Jobs. Simon & Schuster. p. 227. ISBN 978-1-4087-0374-8.
  7. A Practical Guide to Linux Commands, Editors, and Shell Programming, 3rd edition, by Mark G. Sobell, page 2
  8. Linzmayer, Owen W. (1999). Apple Confidential: The Real Story of Apple Computer, Inc.
  9. A Practical Guide to Llinux Commands, Editors, and Shell Programming, 3rd edition by Mark G. Sobell, page 2
  10. Trademark #78257226 for Panther, #78269988 for Tiger, #78270003 for Leopard, #78271630 for Cougar and #78271639 for Lynx, all registered in 2004 by Apple Computer, Inc. "United States Patent and Trademark Office". Retrieved December 20, 2006.
  11. John Siracusa. "Mac OS X Beta – Page 1 – (10/2000)". Ars Technica. Condé Nast Digital. Retrieved March 11, 2010.
  12. "Makefile". Apple. June 2005. Archived from the original on 2009-01-14. Retrieved December 15, 2008. RC Release is Kodiak (Public Beta)
  13. "Mac OS X Public Beta Expires Today | News". The Mac Observer. Retrieved March 11, 2010.
  14. Although the version is now called Cheetah by users, rare evidences can be found to prove that it was called so internally. For instance, a Q&A was created in 2005 which mentions it "Technical Q&A". Apple. October 4, 2005. Retrieved December 20, 2006.
  15. The name Puma can be found here "Cross-Development". Apple. November 11, 2006. Archived from the original on 2007-05-20. Retrieved December 20, 2006.
  16. "Apple Cease-And-Desists Stupidity Leak". Slashdot. 2001. Retrieved November 5, 2008.
  17. "Apple Makes Mac OS X the Default Operating System on All Macs" (Press release). Apple. January 7, 2002. Retrieved December 3, 2006.
  18. "Jaguar "Unleashed" at 10:20 pm Tonight" (Press release). Apple. August 23, 2002. Retrieved December 15, 2008.
  19. The headline of the press release mention "Jaguar", while the codename was not mentioned for earlier versions. See Apple.com, "Jaguar" press release, compared to Mac OS X 10.0 press release and Mac OS X 10.1 press release
  20. "Wayback Machine's Cache of the OS X 10.2 Product Information Page". Apple. August 29, 2002. Archived from the original on August 29, 2002. Retrieved June 12, 2008.
  21. "Apple Previews "Jaguar," the Next Major Release of Mac OS X" (Press release). Apple. May 6, 2002. Retrieved December 20, 2006.
  22. "Apple Announces Mac OS X "Panther"" (Press release). Apple. October 8, 2003. Retrieved January 11, 2007.
  23. "Apple Unleashes "Tiger Friday at 6:00 pm" (Press release). Apple. April 28, 2005. Retrieved January 11, 2007.
  24. "Apple unveils Intel iMacs". AppleInsider. January 2006. Retrieved December 15, 2008.
  25. "Apple – BootCamp". Apple. 2006. Archived from the original on June 2, 2006. Retrieved June 5, 2006.
  26. "Mac OS X Leopard – Technology – UNIX". Leopard Technology Overview. Apple. Retrieved October 26, 2007. Leopard is now an Open Brand UNIX 03 Registered Product, conforming to the SUSv3 and POSIX 1003.1 specifications for the C API, Shell Utilities, and Threads.
  27. "Do Classic applications work with Mac OS X 10.5 or Intel-based Macs?". Knowledge Base. Apple. January 13, 2006. Retrieved October 25, 2007.
  28. Reisinger, Don (January 6, 2011). "Mac App Store launches on Snow Leopard". CNET. CBS Interactive.
  29. Lynch, Steven (June 12, 2008). "Mac OS X Snow Leopard Drops PowerPC Support". HardOCP. Retrieved October 20, 2010.
  30. "Apple – OS X Lion - The world's most advanced desktop operating system.". Apple. October 20, 2010. Retrieved October 20, 2010.
  31. "Apple – OS X Mountain Lion - The world's most advanced desktop operating system.". Apple. February 16, 2012. Retrieved February 16, 2012.
  32. Panzarino, Matthew (February 16, 2012). "Apple courts China with Sina Weibo, Baidu, Youku and more integrated in Mountain Lion". The Next Web. Retrieved March 15, 2012.
  33. "OS X Mountain Lion - See everything the new OS X can do.". Apple. Section "Notes". Retrieved February 22, 2012.
  34. Titlow, John Paul. "Apple's Convergence of Desktop and Mobile Continues With Mountain Lion". ReadWriteWeb. SAY Media. Retrieved 24 April 2012.
  35. "OS X Mountain Lion - Inspired by iPad. Made for the Mac". Apple. Retrieved 2012-03-23.
  36. Cheng, Jacqui. "OS X Mountain Lion now available via Mac App Store". Ars Technica. Retrieved September 1, 2012.
  37. "Apple Releases Developer Preview of OS X Mavericks With More Than 200 New Features" (Press release). Apple Inc. June 10, 2013.
  38. WWDC 2013 Keynote. Apple Inc. June 10, 2013.
  39. Ha, Anthony (Jun 10, 2013). "Apple Has A New, California-Based Naming Scheme For OS X, Starting With OS X Mavericks". TechCrunch.
  40. Souppouris, Aaron (October 22, 2013). "OS X Mavericks now available as a free download". The Verge.
  41. Gupta, Poornima; Chan, Edwin (October 22, 2013). "Apple unveils iPad Air, new Macs for holidays". Reuters.
  42. "Apple - Press Info - Apple Announces OS X El Capitan with Refined Experience & Improved Performance". www.apple.com. Retrieved 2015-10-21.
  43. Dhiraj, Rav (June 2015). "What's New in Metal, Part 1" (pdf). Apple Developer. Apple. p. 84. Retrieved June 17, 2015.
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