What is interrupts ?

Interrupts

In system programming, an interrupt is a signal to the processor emitted by hardware or software indicating an event that needs immediate attention. An interrupt alerts the processor to a high-priority condition requiring the interruption of the current code the processor is executing. The processor responds by suspending its current activities, saving its state, and executing a function called an interrupt handler (or an interrupt service routine, ISR) to deal with the event. This interruption is temporary, and, after the interrupt handler finishes, the processor resumes normal activities.

There are two types of interrupts:

• Hardware Interrupts: These are used by devices to communicate that they require attention from the operating system.Internally, hardware interrupts are implemented using electronic alerting signals that are sent to the processor
• Software Interrupts: These are caused either by an exceptional condition in the processor itself, or a special instruction in the instruction set which causes an interrupt when it is executed

Each interrupt has its own interrupt handler. The number of hardware interrupts is limited by the number of interrupt request (IRQ) lines to the processor, but there may be hundreds of different software interrupts. Interrupts are a commonly used technique for computer multitasking, especially in real-time computing. Such a system is said to be interrupt-driven.

Interrupt handler: an interrupt handler, also known as an interrupt service routine or ISR, is a special block of code associated with a specific interrupt condition. Interrupt handlers are initiated by hardware interrupts, software interrupt instructions, or software exceptions, and are used for implementing device drivers or transitions between protected modes of operation, such as system calls.An interrupt handler is a low-level counterpart of event handlers.

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World Heritage Site

Around the world,there are many places forests, mountains ,lakes ,deserts , monuments, buildings, complexes, or cities which are of universal importance for the cultural or the natural wealth they posses. Such places have been selected by UNITED NATIONS EDUCATIONAL,SCIENTIFIC AND CULTURAL ORGANIZATION (UNESCO) and listed as UNESCO World heritage Sites.Scattered across the planet ,there are about 1031 sites according to July 2015,which include  802 cultural, 197 natural, and 32 mixed properties, in 163 Countries.

 According to the sites ranked by country, Italy is home to the greatest number of World Heritage Sites with 51 sites, followed  China (48), Spain (44), France(41), Germany (40), Mexico (33), and India (32). UNESCO references each World Heritage Site with an identification number; however, new inscriptions often include previous sites now listed as part of larger descriptions. Consequently, the identification numbers exceed 1,200, even though there are fewer on the list.

World Heritage Sites that are noted for their natural wealth are often protected and preserved within national parks.teeming with Wonderful Wildlife ,breathtaking landscapes and exceptional natural beauty

,these sites are much more than just awe-inspiring scenic natural areas to explore and enjoy because many of them tell us just how fascinating nature is in ways more eloquent than words.

 "our  legacy from the past ,what we live with today, and what we pass onto future generations"

These sites are like mirror which, show pasted earth that is how was our earth in pasted days ,like 

THE Grand Canyon National Park in Arizona ,USA ,tells us the story of two billion years of our planet's past.The archaeological site at Mohenjo-daro ,Pakistan,unveils an interesting tale of an ancient civilization . Russia's lake BAIKAL ,the planet deepest lake,center of one of world's richest and most unusual freshwater faunas,which contains 20% of the world's total unfrozen fresh water reserve.It is also the World oldest lake known as "The Peal of Siberia".It is also home of only completely freshwater seal "NERPA" .Many unusual creatures that inhibit the site can not be found anywhere else in the world which are studied by scientists,for uncovering evolution of human ,which make the site of exceptional value to the science evolution.  

LAKE BAIKAL

We have got these heritage sites from our ancestor ,as gift to understand our past and understand it for making our present better and nice.So,we should respect these heritage sites,protect them and enrich them and create other heritage sites, so that our coming generation will feel proud  of these heritage site.

"World Heritage sites are mirror to see the pasted Earth"