Symbian OS history.(ST Series)
Symbian OS is the leading operating system (OS) designed for mobile devices and smartphones, with associated libraries, user interface, frameworks and reference implementations of common tools,originally developed by Symbian Ltd. It was a descendant of Psion'sEPOC and runs exclusively on ARM processors, although an unreleased x86 port existed.
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In 2008, the former Symbian Software Limited was acquired by Nokia and a new independent non-profit organisation called theSymbian Foundation was established. Symbian OS and its associated user interfaces S60, UIQ and MOAP(S) were contributed by their owners to the foundation with the objectiveof creating the Symbian platformas a royalty-free, open source software. The platform has been designated as the successor to Symbian OS, following the official launch of the Symbian Foundation in April 2009. The Symbian platform was officially made available as open source code in February 2010.
Devices based on Symbian OS account for 46.9% of smartphone sales, making it the world's m os t popular mobile operating system.
Design
Symbian features pre-emptive multitasking and memory protection, like other operating systems (especially th os e created for use on desktop computers). EPOC's approach to multitasking was inspired by VMS and is based on asynchronous server-based events.
Symbian OS was created with three systems design principles inmind:
the integrity and security of userdata is paramount,
user time must not be wasted, and
all resources are scarce.
To best follow these principles, Symbian uses a microkernel, has a request-and-callback approach to services, and maintains separation between user interfaceand engine. The OS is optimised for low-power battery-based devices and for ROM-based systems (e.g. features like XIP andre-entrancy in shared libraries). Applications, and the OS itself, follow an object-oriented design: Model-view-controller (MVC).
Later OS iterations diluted this approach in response to market demands, notably with the introduction of a real-time kerneland a platform security model in versions 8 and 9.
There is a strong emphasis on conserving resources which is exemplified by Symbian-specific programming idioms such as descriptors and a cleanup stack. There are similar techniques for conserving disk space (though thedisks on Symbian devices are usually flash memory). Furthermore, all Symbian programming is event-based, and the CPU is switched into a low power mode when applications are not directly dealing with an event. This is achieved through a programming idiom called active objects. Similarly the Symbian approach to threads and processesis driven by reducing overheads.
The Symbian kernel (EKA2) supports sufficiently-fast real-time response to build a single-core phone around it¡ªthat is, a phone in which a single processor core executes both the user applications and the signalling stack[5]. This is a feature which is not available in Linux. This has allowed Symbian EKA2 phones to become smaller, cheaper and more power efficient than their predecessors.
Competition
In the number of "smart mobile device" shipments, Symbian devices are the market leaders. Statistics published in February 2010 showed that the Symbian devices comprised a 47.2% share ofthe smart mobile devices shipped in in 2009, with RIM having 20.8%, Apple having 15.1% (through iPhone OS), Micr os oft having 8.8% (through Windows CEand Windows Mobile) and Google Android having 4.7%. Other competitors include Palm OS, Qualcomm's BREW, SavaJe, Linuxand MontaVista Software.
Although the share of the global smartphone market dropped from52.4% in 2008 to 47.2% in 2009, theshipment volume of Symbian devices grew 4.8%, from 74.9 million units to 78.5 million units.....
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Symbian OS is the leading operating system (OS) designed for mobile devices and smartphones, with associated libraries, user interface, frameworks and reference implementations of common tools,originally developed by Symbian Ltd. It was a descendant of Psion'sEPOC and runs exclusively on ARM processors, although an unreleased x86 port existed.
Recomended Post What is google ranking.
In 2008, the former Symbian Software Limited was acquired by Nokia and a new independent non-profit organisation called theSymbian Foundation was established. Symbian OS and its associated user interfaces S60, UIQ and MOAP(S) were contributed by their owners to the foundation with the objectiveof creating the Symbian platformas a royalty-free, open source software. The platform has been designated as the successor to Symbian OS, following the official launch of the Symbian Foundation in April 2009. The Symbian platform was officially made available as open source code in February 2010.
Devices based on Symbian OS account for 46.9% of smartphone sales, making it the world's m os t popular mobile operating system.
Design
Symbian features pre-emptive multitasking and memory protection, like other operating systems (especially th os e created for use on desktop computers). EPOC's approach to multitasking was inspired by VMS and is based on asynchronous server-based events.
Symbian OS was created with three systems design principles inmind:
the integrity and security of userdata is paramount,
user time must not be wasted, and
all resources are scarce.
To best follow these principles, Symbian uses a microkernel, has a request-and-callback approach to services, and maintains separation between user interfaceand engine. The OS is optimised for low-power battery-based devices and for ROM-based systems (e.g. features like XIP andre-entrancy in shared libraries). Applications, and the OS itself, follow an object-oriented design: Model-view-controller (MVC).
Later OS iterations diluted this approach in response to market demands, notably with the introduction of a real-time kerneland a platform security model in versions 8 and 9.
There is a strong emphasis on conserving resources which is exemplified by Symbian-specific programming idioms such as descriptors and a cleanup stack. There are similar techniques for conserving disk space (though thedisks on Symbian devices are usually flash memory). Furthermore, all Symbian programming is event-based, and the CPU is switched into a low power mode when applications are not directly dealing with an event. This is achieved through a programming idiom called active objects. Similarly the Symbian approach to threads and processesis driven by reducing overheads.
The Symbian kernel (EKA2) supports sufficiently-fast real-time response to build a single-core phone around it¡ªthat is, a phone in which a single processor core executes both the user applications and the signalling stack[5]. This is a feature which is not available in Linux. This has allowed Symbian EKA2 phones to become smaller, cheaper and more power efficient than their predecessors.
Competition
In the number of "smart mobile device" shipments, Symbian devices are the market leaders. Statistics published in February 2010 showed that the Symbian devices comprised a 47.2% share ofthe smart mobile devices shipped in in 2009, with RIM having 20.8%, Apple having 15.1% (through iPhone OS), Micr os oft having 8.8% (through Windows CEand Windows Mobile) and Google Android having 4.7%. Other competitors include Palm OS, Qualcomm's BREW, SavaJe, Linuxand MontaVista Software.
Although the share of the global smartphone market dropped from52.4% in 2008 to 47.2% in 2009, theshipment volume of Symbian devices grew 4.8%, from 74.9 million units to 78.5 million units.....
If You Like This Article Then Hit Like Button Bellow:)
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