The Apache Software Foundation describes the current iteration of Apache Royale as an open-source frontend technology that allows a developer to code in ActionScript 3 and MXML and target web, mobile devices and desktop devices on Apache Cordova all at once. Apache Royale is in beta development stage. Flex uses MXML to define UI layout and other non-visual static aspects, ActionScript to address dynamic aspects and as code-behind, requires Adobe AIR or Flash Player at runtime to run the application. Macromedia targeted the enterprise application development market with its initial releases of Flex 1.0 and 1.5. The company offered the technology at a price around US$15,000 per CPU. Required for deployment, the Java EE application server compiled MXML and ActionScript on-the-fly into Flash applications; each server license included 5 licenses for the Flex Builder IDE. Adobe changed the licensing model for the Flex product line with the release of Flex 2; the core Flex 2 SDK, consisting of the command-line compilers and the complete class library of user interface components and utilities, was made available as a free download.
Complete Flex applications can be built and deployed with the Flex 2 SDK, which contains no limitations or restrictions compared to the same SDK included with the Flex Builder IDE. Adobe based the new version of Flex Builder on the open source Eclipse platform; the company released two versions of Standard and Professional. The Professional version includes the Flex Charting Components library. Enterprise-oriented services remain available through Flex Data Services 2; this server component provides data synchronization, data push, publish-subscribe and automated testing. Unlike Flex 1.0 and 1.5, Flex Data Services is not required for the deployment of Flex applications. Coinciding with the release of Flex 2, Adobe introduced a new version of the ActionScript programming language, known as Actionscript 3, reflecting the latest ECMAScript specification; the use of ActionScript 3 and Flex 2 requires version 9 or of the Flash Player runtime. Flash Player 9 incorporated a new and more robust virtual machine for running the new ActionScript 3.
Flex was the first Macromedia product to be re-branded under the Adobe name. On April 26, 2007 Adobe announced their intent to release the Flex 3 SDK under the terms of the Mozilla Public License. Adobe released the first beta of Flex 3, codenamed Moxie, in June 2007. Major enhancements include integration with the new versions of Adobe's Creative Suite products, support for AIR, the addition of profiling and refactoring tools to the Flex Builder IDE. Adobe released Flex 4.0 on March 22, 2010. The Flex 4 development environment is called Adobe Flash Builder known as Adobe Flex Builder; some themes that have been mentioned by Adobe and have been incorporated into Flex 4 are as follows: Design in Mind: The framework has been designed for continuous collaboration between designers and developers. Accelerated Development: Be able to take application development from conception to reality quickly. Horizontal Platform Improvements: Compiler performance, language enhancements, BiDirectional components, enhanced text.
Full Support for Adobe Flash Player 10 and above. Broadening Horizons: Finding ways to make a framework lighter, supporting more deployment runtimes, runtime MXML. Simpler skinning than the previous versions. Integration with Adobe Flash Catalyst. Custom templatesFlash Builder is available in two versions: Standard and Premium, the premium adds the following features. An update to Flash Builder 4.5 and Flex 4.5 adds support for building Flex applications for BlackBerry Tablet OS and Apple iOS. Flex 4.5 SDK delivers many new components and capabilities, along with integrated support in Flash Builder 4.5 and Flash Catalyst CS 5.5. With the Adobe Flex 4.5 SDK, governed by three main goals: Allow developers to use Flex for multiscreen application development Further mature the Spark architecture and component set, introduced in Flex 4 In November 2011 Adobe released Flex SDK update 4.6, with the following changes: More Spark mobile components i
An operating system is system software that manages computer hardware and software resources and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is executed directly by the hardware and makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers; the dominant desktop operating system is Microsoft Windows with a market share of around 82.74%. MacOS by Apple Inc. is in second place, the varieties of Linux are collectively in third place. In the mobile sector, use in 2017 is up to 70% of Google's Android and according to third quarter 2016 data, Android on smartphones is dominant with 87.5 percent and a growth rate 10.3 percent per year, followed by Apple's iOS with 12.1 percent and a per year decrease in market share of 5.2 percent, while other operating systems amount to just 0.3 percent.
Linux distributions are dominant in supercomputing sectors. Other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running in concurrency; this is achieved by time-sharing, where the available processor time is divided between multiple processes. These processes are each interrupted in time slices by a task-scheduling subsystem of the operating system. Multi-tasking may be characterized in co-operative types. In preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs. Unix-like operating systems, such as Solaris and Linux—as well as non-Unix-like, such as AmigaOS—support preemptive multitasking. Cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking.
32-bit versions of both Windows NT and Win9x, used preemptive multi-tasking. Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem. A multi-user operating system extends the basic concept of multi-tasking with facilities that identify processes and resources, such as disk space, belonging to multiple users, the system permits multiple users to interact with the system at the same time. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources to multiple users. A distributed operating system manages a group of distinct computers and makes them appear to be a single computer; the development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine; when computers in a group work in cooperation, they form a distributed system.
In an OS, distributed and cloud computing context, templating refers to creating a single virtual machine image as a guest operating system saving it as a tool for multiple running virtual machines. The technique is used both in virtualization and cloud computing management, is common in large server warehouses. Embedded operating systems are designed to be used in embedded computer systems, they are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources, they are compact and efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems. A real-time operating system is an operating system that guarantees to process events or data by a specific moment in time. A real-time operating system may be single- or multi-tasking, but when multitasking, it uses specialized scheduling algorithms so that a deterministic nature of behavior is achieved. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
A library operating system is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries and composed with the application and configuration code to construct a unikernel: a specialized, single address space, machine image that can be deployed to cloud or embedded environments. Early computers were built to perform a series of single tasks, like a calculator. Basic operating system features were developed in the 1950s, such as resident monitor functions that could automatically run different programs in succession to speed up processing. Operating systems did not exist in their more complex forms until the early 1960s. Hardware features were added, that enabled use of runtime libraries and parallel processing; when personal computers became popular in the 1980s, operating systems were made for them similar in concept to those used on larger computers. In the 1940s, the earliest electronic digital systems had no operating systems.
Electronic systems of this time were programmed on rows of mechanical switches or by jumper wires on plug boards. These were special-purpose systems that, for example, generated ballistics tables for the military or controlled the pri
MacOS is a series of graphical operating systems developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac family of computers. Within the market of desktop and home computers, by web usage, it is the second most used desktop OS, after Microsoft Windows.macOS is the second major series of Macintosh operating systems. The first is colloquially called the "classic" Mac OS, introduced in 1984, the final release of, Mac OS 9 in 1999; the first desktop version, Mac OS X 10.0, was released in March 2001, with its first update, 10.1, arriving that year. After this, Apple began naming its releases after big cats, which lasted until OS X 10.8 Mountain Lion. Since OS X 10.9 Mavericks, releases have been named after locations in California. Apple shortened the name to "OS X" in 2012 and changed it to "macOS" in 2016, adopting the nomenclature that they were using for their other operating systems, iOS, watchOS, tvOS; the latest version is macOS Mojave, publicly released in September 2018.
Between 1999 and 2009, Apple sold. The initial version, Mac OS X Server 1.0, was released in 1999 with a user interface similar to Mac OS 8.5. After this, new versions were introduced concurrently with the desktop version of Mac OS X. Beginning with Mac OS X 10.7 Lion, the server functions were made available as a separate package on the Mac App Store.macOS is based on technologies developed between 1985 and 1997 at NeXT, a company that Apple co-founder Steve Jobs created after leaving the company. The "X" in Mac OS X and OS X is pronounced as such; the X was a prominent part of the operating system's brand identity and marketing in its early years, but receded in prominence since the release of Snow Leopard in 2009. UNIX 03 certification was achieved for the Intel version of Mac OS X 10.5 Leopard and all releases from Mac OS X 10.6 Snow Leopard up to the current version have UNIX 03 certification. MacOS shares its Unix-based core, named Darwin, many of its frameworks with iOS, tvOS and watchOS.
A modified version of Mac OS X 10.4 Tiger was used for the first-generation Apple TV. Releases of Mac OS X from 1999 to 2005 ran on the PowerPC-based Macs of that period. After Apple announced that they were switching to Intel CPUs from 2006 onwards, versions were released for 32-bit and 64-bit Intel-based Macs. Versions from Mac OS X 10.7 Lion run on 64-bit Intel CPUs, in contrast to the ARM architecture used on iOS and watchOS devices, do not support PowerPC applications. The heritage of what would become macOS had originated at NeXT, a company founded by Steve Jobs following his departure from Apple in 1985. There, the Unix-like NeXTSTEP operating system was developed, launched in 1989; the kernel of NeXTSTEP is based upon the Mach kernel, developed at Carnegie Mellon University, with additional kernel layers and low-level user space code derived from parts of BSD. Its graphical user interface was built on top of an object-oriented GUI toolkit using the Objective-C programming language. Throughout the early 1990s, Apple had tried to create a "next-generation" OS to succeed its classic Mac OS through the Taligent and Gershwin projects, but all of them were abandoned.
This led Apple to purchase NeXT in 1996, allowing NeXTSTEP called OPENSTEP, to serve as the basis for Apple's next generation operating system. This purchase led to Steve Jobs returning to Apple as an interim, the permanent CEO, shepherding the transformation of the programmer-friendly OPENSTEP into a system that would be adopted by Apple's primary market of home users and creative professionals; the project was first code named "Rhapsody" and officially named Mac OS X. Mac OS X was presented as the tenth major version of Apple's operating system for Macintosh computers. Previous Macintosh operating systems were named using Arabic numerals, as with Mac OS 8 and Mac OS 9; the letter "X" in Mac OS X's name refers to a Roman numeral. It is therefore pronounced "ten" in this context. However, it is commonly pronounced like the letter "X"; the first version of Mac OS X, Mac OS X Server 1.0, was a transitional product, featuring an interface resembling the classic Mac OS, though it was not compatible with software designed for the older system.
Consumer releases of Mac OS X included more backward compatibility. Mac OS applications could be rewritten to run natively via the Carbon API; the consumer version of Mac OS X was launched in 2001 with Mac OS X 10.0. Reviews were variable, with extensive praise for its sophisticated, glossy Aqua interface but criticizing it for sluggish performance. With Apple's popularity at a low, the makers of several classic Mac applications such as FrameMaker and PageMaker declined to develop new versions of their software for Mac OS X. Ars Technica columnist John Siracusa, who reviewed every major OS X release up to 10.10, described the early releases in retrospect as'dog-slow, feature poor' and Aqua as'unbearably slow and a huge resource hog'. Apple developed several new releases of Mac OS X. Siracusa's review of version 10.3, noted "It's strange to have gone from years of uncertainty and vaporware to a steady annual supply of major new operating system releases." Version 10.4, Tiger shocked executives at Microsoft by offering a number of features, such as fast file s
In computing, a web application or web app is a client–server computer program which the client runs in a web browser. Common web applications include webmail, online retail sales, online auction; the general distinction between a dynamic web page of any kind and a "web application" is unclear. Web sites most to be referred to as "web applications" are those which have similar functionality to a desktop software application, or to a mobile app. HTML5 introduced explicit language support for making applications that are loaded as web pages, but can store data locally and continue to function while offline. Single-page applications are more application-like because they reject the more typical web paradigm of moving between distinct pages with different URLs. Single-page frameworks like Sencha Touch and AngularJS might be used to speed development of such a web app for a mobile platform. There are several ways of targeting mobile devices when making a web application: Responsive web design can be used to make a web application - whether a conventional website or a single-page application viewable on small screens and work well with touchscreens.
Progressive Web Apps are web applications that load like regular web pages or websites but can offer the user functionality such as working offline, push notifications, device hardware access traditionally available only to native mobile applications. Native apps or "mobile apps" run directly on a mobile device, just as a conventional software application runs directly on a desktop computer, without a web browser. Frameworks like React Native, Flutter and FuseTools allow the development of native apps for all platforms using languages other than each standard native language. Hybrid apps embed a mobile web site inside a native app using a hybrid framework like Apache Cordova and Ionic or Appcelerator Titanium; this allows development using web technologies while retaining certain advantages of native apps. In earlier computing models like client–server, the processing load for the application was shared between code on the server and code installed on each client locally. In other words, an application had its own pre-compiled client program which served as its user interface and had to be separately installed on each user's personal computer.
Cascading Style Sheets
This cascading priority scheme is predictable. The CSS specifications are maintained by the World Wide Web Consortium. Internet media type text/css is registered for use with CSS by RFC 2318; the W3C operates a free CSS validation service for CSS documents. In addition to HTML, other markup languages support the use of CSS including XHTML, plain XML, SVG, XUL. CSS has a simple syntax and uses a number of English keywords to specify the names of various style properties. A style sheet consists of a list of rules; each rule or rule-set consists of one or more selectors, a declaration block. In CSS, selectors declare which part of the markup a style applies to by matching tags and attributes in the markup itself. Selectors may apply to the following: all elements of a specific type, e.g. the second-level headers h2 elements specified by attribute, in particular: id: an identifier unique within the document class: an identifier that can annotate multiple elements in a document elements depending on how they are placed relative to others in the document tree.
Classes and IDs are case-sensitive, start with letters, can include alphanumeric characters and underscores. A class may apply to any number of instances of any elements. An ID may only be applied to a single element. Pseudo-classes are used in CSS selectors to permit formatting based on information, not contained in the document tree. One example of a used pseudo-class is:hover, which identifies content only when the user “points to” the visible element by holding the mouse cursor over it, it is #elementid: hover. A pseudo-class classifies document elements, such as:link or:visited, whereas a pseudo-element makes a selection that may consist of partial elements, such as::first-line or::first-letter. Selectors may be combined in many ways to achieve great flexibility. Multiple selectors may be joined in a spaced list to specify elements by location, element type, id, class, or any combination thereof; the order of the selectors is important. For example, div.myClass applies to all elements of class myClass that are inside div elements, whereas.myClass div applies to all div elements that are in elements of class myClass.
The following table provides a summary of selector syntax indicating usage and the version of CSS that introduced it. A declaration block consists of a list of declarations in braces; each declaration itself consists of a property, a colon, a value. If there are multiple declarations in a block, a semi-colon must be inserted to separate each declaration. Properties are specified in the CSS standard; each property has a set of possible values. Some properties can affect any type of element, others apply only to particular groups of elements. Values may be keywords, such as "center" or "inherit", or numerical values, such as 200px, 50vw or 80%. Color values can be specified with keywords, hexadecimal values, RGB values on a 0 to 255 scale, RGBA values that specify both color and alpha transparency, or HSL or HSLA values. Before CSS, nearly all presentational attributes of HTML documents were contained within the HTML markup. All font colors, background styles, element alignments and sizes had to be explicitly described repeatedly, within the HTML.
CSS lets authors move much of that information to another file, the style sheet, resulting in simpler HTML. For example, sub-headings, sub-sub-headings, etc. are defined structurally using HTML. In print and on the screen, choice of font, size and emphasis for these elements is presentational. Before CSS, document authors who wanted to assign such typographic characteristics to, all h2 headings had to repeat HTML presentational markup for each occurrence of that heading type; this made documents more complex and more error-prone and difficult to maintain. CSS allows the separation of presentation from structure. CSS can define color, text alignment, borders, spacing and many other typographic characteristics, can do so independently for on-screen and printed views. CSS defines non-visual styles, such as reading speed and emphasis for aural text readers; the W3C has now deprecated the use of all presentational HTML markup. For example, under pre-CSS HTML, a heading element defined with red text would be written as: Using CSS, the sam
Mozilla Prism is a discontinued project which integrated web applications with the desktop, allowing web applications to be launched from the desktop and configured independently of the default web browser. As of November 2010, Prism is listed as an inactive project at the Mozilla labs website. Prism is based on a concept called a site-specific browser. An SSB is designed to work with one web application, it doesn't have the menus and other accoutrements of a traditional web browser. The software is built upon XULRunner, so it is possible to get some Mozilla Firefox extensions to work in it; the preview announcement of Prism was made in October 2007. On February 1, 2011, Mozilla labs announced it would no longer maintain Prism, its ideas having been subsumed into a newer project called Chromeless. However, the Mozilla Labs mailing list revealed that Chromeless is not in fact a replacement for Prism, there is no Mozilla replacement for the out-of-the-box site-specific browser functionality of Prism, Chromeless instead being a platform for developers rather than users.
For a while Prism continued to be maintained under the original name of WebRunner, which also was discontinued in September 2011. Chromium Embedded Framework Site-specific browser Rich Internet application Fluid Official website Prism Project at Mozilla Development Center Prism extension for Firefox 3.0 Prism - MozillaWiki prism.mozillalabs.com/ via Internet Archive
Private browsing, privacy mode or incognito mode is a privacy feature in some web browsers to disable browsing history and the web cache. This allows a person to browse the Web without storing local data that could be retrieved at a date. Privacy mode will disable the storage of data in cookies and Flash cookies; this privacy protection is only within the browser application as it may leave traces on the hard drive and memory of the device, or via websites by associating the IP address at the web server. The earliest reference to private browsing was in May 2005, was used to discuss the privacy features in the Safari browser bundled with Mac OS X Tiger; the feature has since been adopted in other browsers, led to popularization of the term in 2008 by mainstream news outlets and computing websites when discussing beta versions of Internet Explorer 8. However, privacy modes operate as shields because browsers do not remove all data from the cache after the session. Plug-ins, like Silverlight, are able to set cookies.
The common web browser plugin Adobe Flash Player began supporting privacy mode in Chrome, Internet Explorer, Safari with the release of version 10.1 in June 2010.. Some browsers allow users to select the privacy mode for single tabs, whereas others create a more isolated environment protected by password and cryptography. Private browsing has multiple uses, including: Reducing history, including autofill and personal information. Performing "pure searches" that are not influenced by prior browsing history or networks or friends' recommendations, which may weight and more rank certain results than others. Preventing accidental saving of login credentials to accounts. Signing into multiple accounts via multiple tabs. Testing websites. Preventing other users of the computer from finding one's search history. Viewing explicit material without outside knowledge; the Mozilla Foundation performed a study about the user behavior when the feature is switched on and how long the session lasts. The results were that most sessions last only about 10 minutes, though there are periods where activation increases.
Private browsing is known by different names in different browsers. In 2012, Brazilian researchers published the results of a research project where they applied forensic techniques to extract information about the users browsing activities on Internet Explorer and Firefox browsers with their private mode enabled, they were able to collect enough data to identify pages visited and partially reconstruct them. This research was extended to include Chrome and Safari browsers; the gathered data proved that browsers' private mode implementations are not able to hide users' browsing activities and that browsers in private mode leave traces of activities in caching structures and files related to the paging process of the operating system. Another independent security analysis, performed by a group of researchers at Newcastle University in 2014, shows a range of security vulnerabilities in the implementation of the private mode across four major browsers; the results are summarized below. Browser extensions are potential threats to the user privacy.
By design, existing browsers choose to enable extensions in the private mode by default. This however allows an installed extension to secretly record the visited websites without the user's awareness. Newer versions of Chrome disable extensions in the private mode by default, but allow the private and the normal modes to run in parallel; this makes it possible for an installed extension in the normal mode to learn the user activities in the private mode by measuring the usage of shared computing resources. Data erasure by the browser alone is found to be insufficient. For example, the records of visited websites during the private session can be retained in memory for a long time after the private session is closed. In addition, the visited website records are kept by the operating system in the local DNS cache. Furthermore, the modified timestamps of certain profile files saved on the disk may reveal if the private mode was turned on and when it was turned on. Software bugs present in some browsers are found to degrade the security of the private mode.
For example, in some earlier versions of Safari, the browser retained private browsing history records if the browser program was not closed or if the user acted to add a bookmark within the private mode. Depending on whether the session is in the private or the normal mode, web browsers exhibit different user interfaces and traffic characteristics; this allows a remote website to tell if the user is in the private mode, for example, by checking the color of the hyperlinks or measuring the time of writing cookies. In 2010, professors at Stanford University found that while Firefox won't record your history during a private browsing session, it still records the sites on which you've installed SSL certificates and allows specific permissions. If you download an SSL certificate from a website or told that site to stop displaying pop-ups and downloading cookies, all of that information is still stored on Firefox. In 2015, researchers from Pennsylvania State University found that a cons