Matthew D. Green
Matthew Daniel Green is a cryptographer and security technologist. Green is an Associate Professor of Computer Science at the Johns Hopkins Information Security Institute, he specializes in applied cryptography, privacy-enhanced information storage systems, anonymous cryptocurrencies, elliptic curve crypto-systems, satellite television piracy. He is a member of the teams that developed the Zerocoin anonymous cryptocurrency and Zerocash.. He has been influential in the development of the Zcash system, he has been involved in the groups that exposed vulnerabilities in RSA Speedpass and E-ZPass. Green received a B. S. from Oberlin College, a B. M. from Oberlin College, a Master's from Johns Hopkins University, a PhD from Johns Hopkins University. His dissertation was titled Cryptography for Secure and Private Databases: Enabling Practical Data Access without Compromising Privacy. Green is the author of the blog, "A Few Thoughts on Cryptographic Engineering". In September 2013, a blog post by Green summarizing and speculating on NSA's programs to weaken cryptography, titled "On the NSA", was controversially taken down by Green's academic dean at Johns Hopkins for "contain a link or links to classified material and the NSA logo".
As Ars Technica notes, this was "a strange request on its face", as this use of the NSA logo by Green was not "reasonably calculated to convey the impression that such use is approved, endorsed, or authorized by the National Security Agency", linking classified information published by news organizations is entirely uncontroversial. The university apologized to Green, the blog post was restored, with a Johns Hopkins spokesman saying that "I'm not saying that there was a great deal of legal analysis done" as explanation for the unmotivated takedown. In addition to general blog posts about NSA, security, Green's blog entries on NSA's backdoor in Dual_EC_DRBG, RSA Security's usage of the backdoored cryptographically secure pseudorandom number generator, have been cited in the mainstream news media. Green holds the position of Associate Professor at the Johns Hopkins Information Security Institute, he teaches courses pertaining to practical cryptography. Green is part of the group which developed an anonymous cryptocurrency protocol.
Zerocoin is a proposed extension to the Bitcoin protocol that would add anonymity to Bitcoin transactions. Zerocoin provides anonymity by the introduction of a separate zerocoin cryptocurrency, stored in the Bitcoin block chain. Though proposed for use with the Bitcoin network, zerocoin could be integrated into any cryptocurrency, his research team has exposed flaws in more than one third of SSL/TLS encrypted web sites as well as vulnerabilities in encryption technologies, including RSA BSAFE, Exxon/Mobil Speedpass, E-ZPass, automotive security systems. In 2015, Green was a member of the research team that identified the Logjam vulnerability in the TLS protocol. Green started his career in 1999 at AT&T Laboratories in New Jersey. At AT&T Labs he worked on a variety of projects including audio coding/secure content distribution, streaming video and wireless localization services; as a graduate student he co-founded Independent Security Evaluators with two fellow students and Avi Rubin in 2005.
Green served as CTO of ISE until his departure in 2011. Green is a member of the technical advisory board for the Linux Foundation Core Infrastructure Initiative, formed to address critical Internet security concerns in the wake of the Heartbleed security bug disclosed in April 2014 in the OpenSSL cryptography library, he sits on the technical advisory boards for CipherCloud and Mozilla Cybersecurity Delphi. Green co-founded and serves on the Board for Directors of the Open Crypto Audit Project, which undertook a security audit of the TrueCrypt software. Matthew D. Green – his personal page at Johns Hopkins University A Few Thoughts on Cryptographic Engineering – his personal crypto blog CE' website – his company page
Google LLC is an American multinational technology company that specializes in Internet-related services and products, which include online advertising technologies, search engine, cloud computing and hardware. It is considered one of the Big Four technology companies, alongside Amazon and Facebook. Google was founded in 1998 by Larry Page and Sergey Brin while they were Ph. D. students at Stanford University in California. Together they own about 14 percent of its shares and control 56 percent of the stockholder voting power through supervoting stock, they incorporated Google as a held company on September 4, 1998. An initial public offering took place on August 19, 2004, Google moved to its headquarters in Mountain View, nicknamed the Googleplex. In August 2015, Google announced plans to reorganize its various interests as a conglomerate called Alphabet Inc. Google is Alphabet's leading subsidiary and will continue to be the umbrella company for Alphabet's Internet interests. Sundar Pichai was appointed CEO of Google.
The company's rapid growth since incorporation has triggered a chain of products and partnerships beyond Google's core search engine. It offers services designed for work and productivity, email and time management, cloud storage, instant messaging and video chat, language translation and navigation, video sharing, note-taking, photo organizing and editing; the company leads the development of the Android mobile operating system, the Google Chrome web browser, Chrome OS, a lightweight operating system based on the Chrome browser. Google has moved into hardware. Google has experimented with becoming an Internet carrier. Google.com is the most visited website in the world. Several other Google services figure in the top 100 most visited websites, including YouTube and Blogger. Google is the most valuable brand in the world as of 2017, but has received significant criticism involving issues such as privacy concerns, tax avoidance, antitrust and search neutrality. Google's mission statement is "to organize the world's information and make it universally accessible and useful".
The companies unofficial slogan "Don't be evil" was removed from the company's code of conduct around May 2018. Google began in January 1996 as a research project by Larry Page and Sergey Brin when they were both PhD students at Stanford University in Stanford, California. While conventional search engines ranked results by counting how many times the search terms appeared on the page, the two theorized about a better system that analyzed the relationships among websites, they called this new technology PageRank. Page and Brin nicknamed their new search engine "BackRub", because the system checked backlinks to estimate the importance of a site, they changed the name to Google. The domain name for Google was registered on September 15, 1997, the company was incorporated on September 4, 1998, it was based in the garage of a friend in California. Craig Silverstein, a fellow PhD student at Stanford, was hired as the first employee. Google was funded by an August 1998 contribution of $100,000 from Andy Bechtolsheim, co-founder of Sun Microsystems.
Google received money from three other angel investors in 1998: Amazon.com founder Jeff Bezos, Stanford University computer science professor David Cheriton, entrepreneur Ram Shriram. Between these initial investors and family Google raised around 1 million dollars, what allowed them to open up their original shop in Menlo Park, California After some additional, small investments through the end of 1998 to early 1999, a new $25 million round of funding was announced on June 7, 1999, with major investors including the venture capital firms Kleiner Perkins and Sequoia Capital. In March 1999, the company moved its offices to Palo Alto, home to several prominent Silicon Valley technology start-ups; the next year, Google began selling advertisements associated with search keywords against Page and Brin's initial opposition toward an advertising-funded search engine. To maintain an uncluttered page design, advertisements were text-based. In June 2000, it was announced that Google would become the default search engine provider for Yahoo!, one of the most popular websites at the time, replacing Inktomi.
In 2003, after outgrowing two other locations, the company leased an office complex from Silicon Graphics, at 1600 Amphitheatre Parkway in Mountain View, California. The complex became known as the Googleplex, a play on the word googolplex, the number one followed by a googol zeroes. Three years Google bought the property from SGI for $319 million. By that time, the name "Google
OS X Mountain Lion
OS X Mountain Lion is the ninth major release of OS X, Apple Inc.'s desktop and server operating system for Macintosh computers. OS X Mountain Lion was released on July 25, 2012 for purchase and download through Apple's Mac App Store, as part of a switch to releasing OS X versions online and every year, rather than every two years or so. Named to signify its status as a refinement of the previous Mac OS X version, Apple's stated aims in developing Mountain Lion were to allow users to more manage and synchronise content between multiple Apple devices and to make the operating system more familiar; the operating system gained the new malware-blocking system Gatekeeper and integration with Apple's online Game Center and iCloud services, while the Safari web browser was updated to version 6. As on iOS, Notes and Reminders became full applications, separate from Mail and Calendar, while the iChat application was replaced with a version of iOS's Messages. Mountain Lion added a version of iOS's Notification Center, which groups updates from different applications in one place.
Integrated links allowing the user to transfer content to Twitter were present in the operating system from launch. Facebook integration was planned but unfinished at launch date, it was released as a downloadable update later. OS X Mountain Lion received positive reviews, with critics praising Notification Center and speed improvements over Mac OS X Lion, while criticizing iCloud for unreliability and Game Center for lack of games. Mountain Lion sold three million units in the first four days, has sold 28 million units as of June 10, 2013, making it Apple's most popular OS X release. Mountain Lion was the last paid upgrade for an OS X major release, with OS X Mavericks and being free. OS X Mountain Lion was announced by Apple on their website on February 16, 2012, as a successor to Mac OS X 10.7 Lion. It achieved golden master status on July 9, 2012. Following a soft transition started with Mac OS X Lion, Apple refers to OS X Mountain Lion as "OS X" rather than "Mac OS X". During the Apple Worldwide Developers Conference keynote on June 11, 2012, Apple announced a "near final" release version of Mountain Lion for developers, with the public version arriving in July 2012 at a price tag of US$19.99.
The third generation MacBook Pro, revised MacBook Air, iPad Smart Case, third-generation AirPort Express were announced at the keynote as well. The specific release date of July 25 was not confirmed until the day before, July 24, by Apple CEO, Tim Cook, as part of Apple's 2012 third-quarter earnings announcement, it was released to the Mac App Store on July 25, 2012, where it sold 3 million units in the first four days of release. An update for Mountain Lion, version 10.8.1, was released on August 23, 2012. It resolved issues with iMessages, Migration Assistant, Microsoft Exchange Server and many other applications. Tests of the update revealed that 10.8.1 improved battery life on laptops, albeit gaining back only half of the battery life, lost in updating to Mountain Lion. Although 10.8.1 improved battery life for some customers, others continue to complain about reduced battery life and a constant drop in battery health resulting in a "Service Battery" message. The official system requirements of OS X 10.8 are 2 GB RAM, 8 GB available storage, OS X 10.6.8 or on any of the following Macs: iMac MacBook, MacBook Pro MacBook Air Mac Mini Mac Pro Xserve As in 10.7, the earliest models supporting AirDrop are the late-2008 MacBook Pro, late-2010 MacBook Air, late-2008 MacBook, mid-2010 Mac Mini, early-2009 Mac Pro with an AirPort Extreme card.
Any Mac released in or after 2011, except the MacBook, supports AirPlay Mirroring. Power Nap is supported on the MacBook Pro with Retina display; the technical basis for these requirements is incompatibility with 32-bit EFI and 32-bit kernel extensions. In order to prevent incompatible systems from installing 10.8, the installer contains a whitelist of supported motherboard IDs. Users have bypassed these limitations so that 10.8 may run with varying functionality on some unsupported computers. Notification Center was added in the operating system, it provides an overview of alerts from applications and displays notifications until the user completes an associated action, rather than requiring instant resolution. Users may choose what applications appear in Notification Center, how they are handled. There are three types of notifications: banners and badges. Banners are displayed for a short period of time in the upper right corner of the Mac's screen, slide off to the right; the icon of the application is displayed on the left side of the banner, while the message from the application will be displayed on the right side.
Alerts will not disappear from the screen until the user takes action. Badges are red notification icons, they indicate the number of items available for the application. Notification Center can be accessed by clicking the icon in the right corner of the menu bar; when open, the user can click a button to tweet, post status updates to Facebook, or view all notifications in the sidebar pane. Swiping up will reveal the option to disable Notification Center for on
The Macintosh is a family of personal computers designed and sold by Apple Inc. since January 1984. The original Macintosh was the first mass-market personal computer that featured a graphical user interface, built-in screen and mouse. Apple sold the Macintosh alongside its popular Apple II family of computers for ten years before they were discontinued in 1993. Early Macintosh models were expensive, hindering its competitiveness in a market dominated by the Commodore 64 for consumers, as well as the IBM Personal Computer and its accompanying clone market for businesses. Macintosh systems still found success in education and desktop publishing and kept Apple as the second-largest PC manufacturer for the next decade. In the early 1990s, Apple introduced models such as the Macintosh LC II and Color Classic which were price-competitive with Wintel machines at the time. However, the introduction of Windows 3.1 and Intel's Pentium processor which beat the Motorola 68040 in most benchmarks took market share from Apple, by the end of 1994 Apple was relegated to third place as Compaq became the top PC manufacturer.
After the transition to the superior PowerPC-based Power Macintosh line in the mid-1990s, the falling prices of commodity PC components, poor inventory management with the Macintosh Performa, the release of Windows 95 saw the Macintosh user base decline. Prompted by the returning Steve Jobs' belief that the Macintosh line had become too complex, Apple consolidated nearly twenty models in mid-1997 down to four in mid-1999: The Power Macintosh G3, iMac, 14.1" PowerBook G3, 12" iBook. All four products were critically and commercially successful due to their high performance, competitive prices and aesthetic designs, helped return Apple to profitability. Around this time, Apple phased out the Macintosh name in favor of "Mac", a nickname, in common use since the development of the first model. Since their transition to Intel processors in 2006, the complete lineup is based on said processors and associated systems, its current lineup includes four desktops, three laptops. Its Xserve server was discontinued in 2011 in favor of the Mac Mac Pro.
Apple has developed a series of Macintosh operating systems. The first versions had no name but came to be known as the "Macintosh System Software" in 1988, "Mac OS" in 1997 with the release of Mac OS 7.6, retrospectively called "Classic Mac OS". In 2001, Apple released Mac OS X, a modern Unix-based operating system, rebranded to OS X in 2012, macOS in 2016; the current version is macOS Mojave, released on September 24, 2018. Intel-based Macs are capable of running non-Apple operating systems such as Linux, OpenBSD, Microsoft Windows with the aid of Boot Camp or third-party software. Apple produced a Unix-based operating system for the Macintosh called A/UX from 1988 to 1995, which resembled contemporary versions of the Macintosh system software. Apple does not license macOS for use on non-Apple computers, however System 7 was licensed to various companies through Apple's Macintosh clone program from 1995 to 1997. Only one company, UMAX Technologies was licensed to ship clones running Mac OS 8.
Since Apple's transition to Intel processors, there is a sizeable community around the world that specialises in hacking macOS to run on non-Apple computers, which are called "Hackintoshes". The Macintosh project began in 1979 when Jef Raskin, an Apple employee, envisioned an easy-to-use, low-cost computer for the average consumer, he wanted to name the computer after his favorite type of apple, the McIntosh, but the spelling was changed to "Macintosh" for legal reasons as the original was the same spelling as that used by McIntosh Laboratory, Inc. the audio equipment manufacturer. Steve Jobs requested that McIntosh Laboratory give Apple a release for the newly spelled name, thus allowing Apple to use it; the request was denied, forcing Apple to buy the rights to use this name. In 1978, Apple began to organize the Apple Lisa project, aiming to build a next-generation machine similar to an advanced Apple II or the yet-to-be-introduced IBM PC. In 1979, Steve Jobs learned of the advanced work on graphical user interfaces taking place at Xerox PARC.
He arranged for Apple engineers to be allowed to visit PARC to see the systems in action. The Apple Lisa project was redirected to utilize a GUI, which at that time was well beyond the state of the art for microprocessor capabilities. Things had changed with the introduction of the 32-bit Motorola 68000 in 1979, which offered at least an order of magnitude better performance than existing designs, made a software GUI machine a practical possibility; the basic layout of the Lisa was complete by 1982, at which point Jobs's continual suggestions for improvements led to him being kicked off the project. At the same time that the Lisa was becoming a GUI machine in 1979, Jef Raskin started the Macintosh project; the design at that time was for a easy-to-use machine for the average consumer. In
Johns Hopkins University
Johns Hopkins University is a private research university in Baltimore, Maryland. Founded in 1876, the university was named for its first benefactor, the American entrepreneur and philanthropist Johns Hopkins, his $7 million bequest —of which half financed the establishment of Johns Hopkins Hospital—was the largest philanthropic gift in the history of the United States up to that time. Daniel Coit Gilman, inaugurated as the institution's first president on February 22, 1876, led the university to revolutionize higher education in the U. S. by integrating teaching and research. Adopting the concept of a graduate school from Germany's ancient Heidelberg University, Johns Hopkins University is considered the first research university in the United States. Over the course of several decades, the university has led all U. S. universities in annual research and development expenditures. In fiscal year 2016, Johns Hopkins spent nearly $2.5 billion on research. Johns Hopkins is organized into 10 divisions on campuses in Maryland and Washington, D.
C. with international centers in Italy and Singapore. The two undergraduate divisions, the Zanvyl Krieger School of Arts and Sciences and the Whiting School of Engineering, are located on the Homewood campus in Baltimore's Charles Village neighborhood; the medical school, the nursing school, the Bloomberg School of Public Health are located on the Medical Institutions campus in East Baltimore. The university consists of the Peabody Institute, the Applied Physics Laboratory, the Paul H. Nitze School of Advanced International Studies, the School of Education, the Carey Business School, various other facilities. Johns Hopkins was a founding member of the American Association of Universities. Johns Hopkins University is cited as among the world's top universities; the university is ranked 10th among undergraduate programs at National Universities in U. S. News & World Report latest rankings, 10th among global universities by U. S. News & World Report in its 2019 rankings, as well as 12th globally in the Times Higher Education World University Rankings.
Over the course of more than 140 years, 37 Nobel laureates and 1 Fields Medalist have been affiliated with Johns Hopkins. Founded in 1883, the Blue Jays men's lacrosse team has captured 44 national titles and joined the Big Ten Conference as an affiliate member in 2014. On his death in 1873, Johns Hopkins, a Quaker entrepreneur and childless bachelor, bequeathed $7 million to fund a hospital and university in Baltimore, Maryland. At that time this fortune, generated from the Baltimore and Ohio Railroad, was the largest philanthropic gift in the history of the United States; the first name of philanthropist Johns Hopkins is the surname of his great-grandmother, Margaret Johns, who married Gerard Hopkins. They named their son Johns Hopkins. Samuel named one of his sons for his father and that son would become the university's benefactor. Milton Eisenhower, a former university president, once spoke at a convention in Pittsburgh where the Master of Ceremonies introduced him as "President of John Hopkins."
Eisenhower retorted that he was "glad to be here in Pittburgh." The original board opted for an novel university model dedicated to the discovery of knowledge at an advanced level, extending that of contemporary Germany. Building on the Humboldtian model of higher education, the German education model of Wilhelm von Humboldt, it became dedicated to research. Johns Hopkins thereby became the model of the modern research university in the United States, its success shifted higher education in the United States from a focus on teaching revealed and/or applied knowledge to the scientific discovery of new knowledge. The trustees worked alongside four notable university presidents – Charles W. Eliot of Harvard, Andrew D. White of Cornell, Noah Porter of Yale College and James B. Angell of Michigan, they each vouched for Daniel Coit Gilman to lead the new University and he became the university's first president. Gilman, a Yale-educated scholar, had been serving as president of the University of California prior to this appointment.
In preparation for the university's founding, Gilman visited University of Freiburg and other German universities. Gilman launched what many at the time considered an audacious and unprecedented academic experiment to merge teaching and research, he dismissed the idea that the two were mutually exclusive: "The best teachers are those who are free and willing to make original researches in the library and the laboratory," he stated. To implement his plan, Gilman recruited internationally known luminaries such as the mathematician James Joseph Sylvester. Gilman focused on the expansion of graduate support of faculty research; the new university fused advanced scholarship with such professional schools as medicine and engineering. Hopkins became the national trendsetter in doctoral programs and the host for numerous scholarly journals and associations; the Johns Hopkins University Press, founded in 1878, is the oldest American university press in continuous operation. With the completion of Johns Hopkins Hospital in 1889 and the medical school in 1893, the university's research-focused mode of instruction soon began attracting world-renowned faculty members who would become major figures in the emerging field of acad
Apple Inc. is an American multinational technology company headquartered in Cupertino, that designs and sells consumer electronics, computer software, online services. It is considered one of the Big Four of technology along with Amazon and Facebook; the company's hardware products include the iPhone smartphone, the iPad tablet computer, the Mac personal computer, the iPod portable media player, the Apple Watch smartwatch, the Apple TV digital media player, the HomePod smart speaker. Apple's software includes the macOS and iOS operating systems, the iTunes media player, the Safari web browser, the iLife and iWork creativity and productivity suites, as well as professional applications like Final Cut Pro, Logic Pro, Xcode, its online services include the iTunes Store, the iOS App Store, Mac App Store, Apple Music, Apple TV+, iMessage, iCloud. Other services include Apple Store, Genius Bar, AppleCare, Apple Pay, Apple Pay Cash, Apple Card. Apple was founded by Steve Jobs, Steve Wozniak, Ronald Wayne in April 1976 to develop and sell Wozniak's Apple I personal computer, though Wayne sold his share back within 12 days.
It was incorporated as Apple Computer, Inc. in January 1977, sales of its computers, including the Apple II, grew quickly. Within a few years and Wozniak had hired a staff of computer designers and had a production line. Apple went public in 1980 to instant financial success. Over the next few years, Apple shipped new computers featuring innovative graphical user interfaces, such as the original Macintosh in 1984, Apple's marketing advertisements for its products received widespread critical acclaim. However, the high price of its products and limited application library caused problems, as did power struggles between executives. In 1985, Wozniak departed Apple amicably and remained an honorary employee, while Jobs and others resigned to found NeXT; as the market for personal computers expanded and evolved through the 1990s, Apple lost market share to the lower-priced duopoly of Microsoft Windows on Intel PC clones. The board recruited CEO Gil Amelio to what would be a 500-day charge for him to rehabilitate the financially troubled company—reshaping it with layoffs, executive restructuring, product focus.
In 1997, he led Apple to buy NeXT, solving the failed operating system strategy and bringing Jobs back. Jobs pensively regained leadership status, becoming CEO in 2000. Apple swiftly returned to profitability under the revitalizing Think different campaign, as he rebuilt Apple's status by launching the iMac in 1998, opening the retail chain of Apple Stores in 2001, acquiring numerous companies to broaden the software portfolio. In January 2007, Jobs renamed the company Apple Inc. reflecting its shifted focus toward consumer electronics, launched the iPhone to great critical acclaim and financial success. In August 2011, Jobs resigned as CEO due to health complications, Tim Cook became the new CEO. Two months Jobs died, marking the end of an era for the company. Apple is well known for its size and revenues, its worldwide annual revenue totaled $265 billion for the 2018 fiscal year. Apple is the world's largest information technology company by revenue and the world's third-largest mobile phone manufacturer after Samsung and Huawei.
In August 2018, Apple became the first public U. S. company to be valued at over $1 trillion. The company employs 123,000 full-time employees and maintains 504 retail stores in 24 countries as of 2018, it operates the iTunes Store, the world's largest music retailer. As of January 2018, more than 1.3 billion Apple products are in use worldwide. The company has a high level of brand loyalty and is ranked as the world's most valuable brand. However, Apple receives significant criticism regarding the labor practices of its contractors, its environmental practices and unethical business practices, including anti-competitive behavior, as well as the origins of source materials. Apple Computer Company was founded on April 1, 1976, by Steve Jobs, Steve Wozniak, Ronald Wayne; the company's first product is the Apple I, a computer designed and hand-built by Wozniak, first shown to the public at the Homebrew Computer Club. Apple I was sold as a motherboard —a base kit concept which would now not be marketed as a complete personal computer.
The Apple I went on sale in July 1976 and was market-priced at $666.66. Apple Computer, Inc. was incorporated on January 3, 1977, without Wayne, who had left and sold his share of the company back to Jobs and Wozniak for $800 only twelve days after having co-founded Apple. Multimillionaire Mike Markkula provided essential business expertise and funding of $250,000 during the incorporation of Apple. During the first five years of operations revenues grew exponentially, doubling about every four months. Between September 1977 and September 1980, yearly sales grew from $775,000 to $118 million, an average annual growth rate of 533%; the Apple II invented by Wozniak, was introduced on April 16, 1977, at the first West Coast Computer Faire. It differs from its major rivals, the TRS-80 and Commodore PET, because of its character cell-based color graphics and open architecture. While early Apple II models use ordinary cassette tapes as storage devices, they were superseded by the introduction of a 5 1⁄4-inch floppy disk drive and interface called the Disk II.
The Apple II was chosen to be the desktop platform for the first "killer app" of the business world: VisiCalc, a spreadsheet program. VisiCalc created a business market for the Apple II and gave home users an additional reason to buy an Apple II: compatibility with the office. Before VisiCalc, Apple had been a distant third place c
A computing platform or digital platform is the environment in which a piece of software is executed. It may be the hardware or the operating system a web browser and associated application programming interfaces, or other underlying software, as long as the program code is executed with it. Computing platforms have different abstraction levels, including a computer architecture, an OS, or runtime libraries. A computing platform is the stage. A platform can be seen both as a constraint on the software development process, in that different platforms provide different functionality and restrictions. For example, an OS may be a platform that abstracts the underlying differences in hardware and provides a generic command for saving files or accessing the network. Platforms may include: Hardware alone, in the case of small embedded systems. Embedded systems can access hardware directly, without an OS. A browser in the case of web-based software; the browser itself runs on a hardware+OS platform, but this is not relevant to software running within the browser.
An application, such as a spreadsheet or word processor, which hosts software written in an application-specific scripting language, such as an Excel macro. This can be extended to writing fully-fledged applications with the Microsoft Office suite as a platform. Software frameworks. Cloud computing and Platform as a Service. Extending the idea of a software framework, these allow application developers to build software out of components that are hosted not by the developer, but by the provider, with internet communication linking them together; the social networking sites Twitter and Facebook are considered development platforms. A virtual machine such as the Java virtual machine or. NET CLR. Applications are compiled into a format similar to machine code, known as bytecode, executed by the VM. A virtualized version of a complete system, including virtualized hardware, OS, storage; these allow, for instance, a typical Windows program to run on. Some architectures have multiple layers, with each layer acting as a platform to the one above it.
In general, a component only has to be adapted to the layer beneath it. For instance, a Java program has to be written to use the Java virtual machine and associated libraries as a platform but does not have to be adapted to run for the Windows, Linux or Macintosh OS platforms. However, the JVM, the layer beneath the application, does have to be built separately for each OS. AmigaOS, AmigaOS 4 FreeBSD, NetBSD, OpenBSD IBM i Linux Microsoft Windows OpenVMS Classic Mac OS macOS OS/2 Solaris Tru64 UNIX VM QNX z/OS Android Bada BlackBerry OS Firefox OS iOS Embedded Linux Palm OS Symbian Tizen WebOS LuneOS Windows Mobile Windows Phone Binary Runtime Environment for Wireless Cocoa Cocoa Touch Common Language Infrastructure Mono. NET Framework Silverlight Flash AIR GNU Java platform Java ME Java SE Java EE JavaFX JavaFX Mobile LiveCode Microsoft XNA Mozilla Prism, XUL and XULRunner Open Web Platform Oracle Database Qt SAP NetWeaver Shockwave Smartface Universal Windows Platform Windows Runtime Vexi Ordered from more common types to less common types: Commodity computing platforms Wintel, that is, Intel x86 or compatible personal computer hardware with Windows operating system Macintosh, custom Apple Inc. hardware and Classic Mac OS and macOS operating systems 68k-based PowerPC-based, now migrated to x86 ARM architecture based mobile devices iPhone smartphones and iPad tablet computers devices running iOS from Apple Gumstix or Raspberry Pi full function miniature computers with Linux Newton devices running the Newton OS from Apple x86 with Unix-like systems such as Linux or BSD variants CP/M computers based on the S-100 bus, maybe the earliest microcomputer platform Video game consoles, any variety 3DO Interactive Multiplayer, licensed to manufacturers Apple Pippin, a multimedia player platform for video game console development RISC processor based machines running Unix variants SPARC architecture computers running Solaris or illumos operating systems DEC Alpha cluster running OpenVMS or Tru64 UNIX Midrange computers with their custom operating systems, such as IBM OS/400 Mainframe computers with their custom operating systems, such as IBM z/OS Supercomputer architectures Cross-platform Platform virtualization Third platform Ryan Sarver: What is a platform