Open Source Software

Open source refers to a program or software in which the source code (the form of the program when a programmer writes a program in a particular programming language) is available to the general public for use and/or modification from its original design free of charge.

Open source code is typically created as a collaborative effort in which programmers improve upon the code and share the changes within the community.

The rationale for this movement is that a larger group of programmers not concerned with proprietary ownership or financial gain will produce a more useful and bug-free product for everyone to use. The concept relies on peer review to find and eliminate bugs in the program code, a process that commercially developed and packaged programs do not employ.

The basics behind the Open Source Initiative is that when programmers can read, redistribute and modify the source code for a piece of software, the software evolves. Open source sprouted in the technological community as a response to proprietary software owned by corporations.

Proprietary software is privately owned and controlled. In the computer industry, proprietary is considered the opposite of open. A proprietary design or technique is one that is owned by a company. It also implies that the company has not divulged specifications that would allow other companies to duplicate the product.

First Computer Virus

If you’ve been using computers every now and then, you definitely know about viruses, and if you’ve been reading my blog, then most likely you’ve seen a lot of my topics about computer virus, malware and worm. Whatever name they have, they only mean one thing –headache. Do you know that the first ever computer virus was born in 1971 and named the creeper virus? Creeper virus started on scientific and military network known as the ARPANET. Creeper virus was actually a self replicating program created by Bob Thomas that infected the DEC PDP-10 computers across the network. Nowadays, we consider this type of viruses as worm. This virus, upon replicating itself into machine that it accessed would broadcast “I’m the creeper, catch me if you can!” on the terminal screen. The reaper, which is the first virus removal program was the one who caught the creeper. The next virus was created 10 years after.

Hard Disk

Nearly every desktop computer and server in use today contains one or more hard-disk drives. Every mainframe and supercomputer is normally connected to hundreds of them. You can even find VCR-type devices and camcorders that use hard disks instead of tape. These billions of hard disks do one thing well -- they store changing digital information in a relatively permanent form. They give computers the ability to remember things when the power goes out.

In this article, we'll take apart a hard disk so that you can see what's inside, and also discuss how they organize the gigabytes of information they hold in files!

A hard disk is part of a unit, often called a "disk drive," "hard drive," or "hard disk drive," that stores and provides relatively quick access to large amounts of data on an electromagnetically charged surface or set of surfaces. Today's computers typically come with a hard disk that contains several billion bytes (gigabytes) of storage.

A hard disk is really a set of stacked "disks," each of which, like phonograph

records, has data recorded electromagnetically in concentric circles or "tracks" on the disk. A "head" (something like a phonograph arm but in a relatively fixed position) records (writes) or reads the information on the tracks. Two heads, one on each side of a disk, read or write the data as the disk spins. Each read or write operation requires that data be located, which is an operation called a "seek." (Data already in a disk cache, however, will be located more quickly.)

A hard disk/drive unit comes with a set rotation speed varying from 4500 to 7200 rpm. Disk access time is measured in milliseconds. Although the physical location can be identified with cylinder, track, and sector locations, these are actually mapped to a logical block address (LBA) that works with the larger address range on today's hard disks.
Related glossary terms: magnetoresistive head technology, yottabyte, serverless backup, byte, partition, InfiniBand, failover, RAMAC (random access method of accounting and control), Fibre Channel, continuous data protection (storage convergence).

Hard Disk Basics

Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes. They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product). They later became known as "hard disks" to distinguish them from "floppy disks." Hard disks have a hard platter that holds the magnetic medium, as opposed to the flexible plastic film found in tapes and floppies.

At the simplest level, a hard disk is not that different from a cassette tape. Both hard disks and cassette tapes use the same magnetic recording techniques described in How Tape Recorders Work. Hard disks and cassette tapes also share the major benefits of magnetic storage -- the magnetic medium can be easily erased and rewritten, and it will "remember" the magnetic flux patterns stored onto the medium for many years.

In the next section, we'll talk about the main differences between casette tapes and hard disks.

Inside: Electronics Board

The best way to understand how a hard disk works is to take a look inside. (Note that OPENING A HARD DISK RUINS IT, so this is not something to try at home unless you have a defunct drive.)

Here is a typical hard-disk drive:

­It is a sealed aluminum box with controller electronics attached to one side. The electronics control the read/write mechanism and the motor that spins the platters. The electronics also assemble the magnetic domains on the drive into bytes (reading) and turn bytes into magnetic domains (writing). The electronics are all contained on a small board that detaches from the rest of the drive:

USB

Just about any computer that you buy today comes with one or more Universal Serial Bus connectors. These USB connectors let you attach mice, printers and other accessories to your computer quickly and easily. The operating system supports USB as well, so the installation of the device drivers is quick and easy, too. Compared to other ways of connecting devices to your computer (including parallel ports, serial ports and special cards that you install inside the computer's case), USB devices are incredibly simple.

­In this article, we'll look at USB ports from both a user and a technical standpoint. You'll learn why the USB system is so flexible and how it's able to support so many devices so easily -- it's truly an amazing system.

Anyone who has been around computers for a while knows the problem that the Universal Serial Bus is trying to solve -- in the past, connecting devices to computers has been a real headache.

Printers connected to parallel printer ports, and most computers only came with one. Things like external storage media, which need a high-speed connection into the computer, would use the parallel port as well, often with limited success and not much speed.
Modems used the serial port, but so did some printers and a variety of odd things like personal digital assistants (PDAs) and digital cameras. Most computers had at most two serial ports, and they were very slow in most cases.
Devices that needed faster connections came with their own cards, which had to fit in a card slot inside the computer's case. Unfortunately, the number of card slots is limited and some of the cards are difficult to install.

The goal of USB is to end all of these headaches. The Universal Serial Bus gives you a single, standardized, easy-to-use way to connect up to 127 devices to a computer.

Just about every peripheral made now comes in a USB version. A sample list of USB devices that you can buy today includes:

Printers
Scanners
Mice
Joysticks
Flight yokes
Digital cameras
Webcams
Scientific data acquisition devices
Modems
Speakers
Telephones
Video phones
Storage devices
Network connections

Connecting a USB device to a computer is simple -- you find the USB connector on the back of your machine and plug the USB connector into it.

If it's a new device, the operating system auto-detects it and asks for the driver disk. If the device has already been installed, the computer activates it and starts talking to it. USB devices can be connected and disconnected at any time.

A typical USB connector, called an "A" connection

Many USB devices come with their own built-in cable, and the cable has an "A" connection on it. If not, then the device has a socket on it that accepts a USB "B" connector.

A typical "B" connection

The USB standard uses "A" and "B" connectors to avoid confusion:

"A" connectors head "upstream" toward the computer.
"B" connectors head "downstream" and connect to individual devices.

By using different connectors on the upstream and downstream end, it's impossible to ever get confused -- if you connect any USB cable's "B" connector into a device, you know that it'll work. Similarly, you can plug any "A" connector into any "A" socket and know that it'll work.

MONITORS - The display unit

Hello Friends,

After all the technical know how of CPU, I move along to one of the most important part of a Computer that is, the display unit - MONITOR. Often referred to as a display screen, a video display terminal (VDT) or visual display unit (VDU), monitor is the component of your computer system that displays the messages and data being processes and utilized by CPU.

There are two types of monitors available in the market. CRT and LCD monitors.
Lets look at them in detail and decide which one would be a better choice for your computing needs.

CRT Monitors: Short for Cathode-ray tubes, these were the only choice consumers had for monitors for many years. CRT has been in use for more than 100 years and is found in most televisions and computer monitors. A CRT works by moving an electron beam back and forth across teh back of screen, each time the beam makes a pass across the screen, it lights up phosphor dots on inside of glass tube, thereby illuminating the active portions of the screen. By drawing many such lines all over the screen it creates an entire screen of images.


LCD Monitors: Short for Liquid Crystal Display, LCD can be found in digital watches and computer monitors. These have sheets of polarizing material with a liquid crystal solution between them. An electric current pass through the liquid causes the crystals to align so that light cannot pass through them. Each crystal is like Shutter, either allowing or blocking light. Color LCD uses two basic techniques for producing color: Passive Matrix - a less expensive technology of two and Thin Film Transistor or Active Matrix that produces color images that are as sharp as CRTs but are expensive.


Let us compare CRT and LCD with respect to the necessary features of a monitor.

Resolution and Viewing Quality: Resolution on CRT is flexible and supports resolution up to 1600 X 1200 and higher, while on LCD it is fixed. The resolution of LCD can be changed but if you change it to other than native resolution you will notice a drop in image quality.

Both type of monitors provide bright and vibrant color display, however LCDs cannot display the maximum color range that a CRT can. In term of image sharpness, when running at native resolution, LCD's picture quality is very sharp while on CRT ,it can be blemished by soft edges or a flawed focus.

A CRT monitor can be viewed from any angle while LCD have a bit of problem. With different angles and distance your view changes in LCD and you may notice picture fade and possibly look as if it will disappear from view. Though recent LCD's provide viewing angle of 179 degrees which is at par with CRTs.

Refresh Rate: This an important feature to look for. CRT call this their Refresh Rate while LCD have this what is called Response time. This simply means the screen will refresh at a given interval. For instance CRT monitor's refresh rate is ~ 75 MHz while a LCD have a response time of 20 to 8 milliseconds. Again faster the refresh rate, better it will be for your eyes.

Gamers and people who watch a lot of movies on LCD screens would be better opting for something with a fast response time, around 8 ms as this reduces the ghosting effect of fast motion.

Brightness: Because LCDs require their own back light to create colour, brightness is an important factor. It's measured in candelas per metre squared or cd/m2, where one candle produces a brightness of 1 candela. The higher this number, the brighter the screen.

Contrast Ratio: This is the degree of difference between the extremes of light and dark colors. The higher the contrast ratio, the more detailed the image will be. Blacks will be blacker, whites will be whiter, and particularly text on the image will be more vivid. It will usually be written as 2000:1 or 1000:1

Screen (Viewable) Size: Most people tend to look at a 17 inch CRT or bigger. When you purchase a 17 inch CRT you usually get 16 inches or a bit more actual viewing area. This is due to bulky frame of CRT. If you purchase a 17 inch LCD monitor you get actual viewing area which is 17 inch or a little less.

Physical Size: There is no denying that LCD wins in terms of physical size and the space it needs. CRT are big, bulky and heavy.

Physical Size of LCD and CRT

Video Card compatibility: It goes without saying that when you are looking at new monitors you should also look at your video card. Make sure that your video card can support the recommended refresh rate and resolution of your monitor. This will help extend the life of both your monitor and your eyes.

Warranty: The manufacturer's warranty is also something to consider when purchasing a new monitor. CRT monitors have a tendency to fail after 3 years and LCD monitors are usually rated from 10 to 50 thousand hours of operation. The longer the warranty the better chance you will have at getting it replaced if and when it does fail.

Price: As an individual one time purchase LCD will be a bit more expensive but throughout lifetime they are cheaper has they have longer lifespan and lower power consumption. The cost of both technologies have come down over the past few years and expect even more sliding. You may pay more for LCD but considering the actual size you get, the money to size advantage is still with LCD.
To sum it up, Here are PROS and CONS of CRT and LCD

CRT MONITOR

PROS: Great value for money, Mature technology, Good for graphical detail, Can accommodate many different resolutions.

CONS: Big, Take up a lot of space, Cost more to run than an LCD

LCD MONITOR

PROS: Less desk space needed, Require less power to run, more environmentally friendly, Increased Viewable area, Faster response time aids in image sharpness.

I hope this information was useful to you and will help you deciding which monitor to buy. In my opinion LCD are preferable over CRT. Though it varies from user to user.

Please feel free to comment on anything to everything. Your valuable advice will help me improve better.

Graphics Cards

Hello Friends,

Today's topic is Graphics Card. One of the most important part of any processor and motherboard is the graphics. I will elaborate on various aspects of Graphics Card and help you choose one and if need be overclock graphics card to get the best out of it.

There are two types of Graphics Card: On-Board Graphics and Stand Alone Graphics.

On-Board Graphics are the ones which are integrated with the processor and share memory with RAM.
Stand Alone Graphics are card which comes as a seperate units that have dedicated memory that is not shared with RAM.

What is GPU ?????

A Graphics Processing Unit or GPU (also occasionally called visual processing unit or VPU) is a dedicated graphics rendering device for a pc, workstation or gaming console. Modern GPUs are very efficient at manipulating and displaying computer graphics, and their highly parallel structure makes them more effective than general-purpose CPUs for a range of complex algorithms. A GPU can sit on top of a video card, or it can be integrated directly into the motherboard.


Graphics boards aren't just for gamers. They help you work with large graphics, play high-definition video, and upgrade the monitor ports on an aging PC. Some models even give you the kind of video inputs and outputs required to hook up your camcorder or cable TV to the PC.

The million dollar question is HOW TO BUY A GRAPHICS BOARD? that is suitable for your computing needs and doesn't break your bank balance.
Read along for details.

THE BIG PICTURE
Graphics chip and board makers update their hardware every six months or so, mainly to enable the development of more-complex, more-realistic PC games. But games aren't the only reason to get a new graphics board. Such features as support for two or even three displays, DVI ports, a TV and/or FM radio tuner, and video connections--such as S-Video, Component, and, looking forward, HDMI--are other compelling reasons to upgrade.

KEY FEATURES
Interface: Today's consumer graphics boards come with a PCI Express interface to plug into a PC's PCI Express slot. A few mainstream and value options with an AGP interface plug into the AGP slot on an older PC. You can't plug a PCI Express card into an AGP slot or vice versa. PCI Express graphics boards transfer data faster than AGP boards.

Graphics processor: Today's graphics chips can efficiently handle sophisticated full-motion 3D video, thanks to advanced graphics processors, or GPUs. Right now, the GPUs populating most graphics boards for desktop PCs are developed by two companies: nVidia and ATI.

Memory: These days, you'll easily find budget graphics cards with at least 256MB of DDR3 SDRAM. You'll want this amount at a minimum, since, for Windows Vista, Microsoft's initial recommendations are to have a graphics board with 128MB of memory to run Vista's Aero Glass graphics-heavy interface. For older games, 128MB is sufficient, though it's best to get a card with at least 256MB of video memory. Many games today don't require more than that, but you may want to opt for more memory rather than face upgrading again when new memory-intensive games arrive.

Some graphics chips that are integrated on a motherboard use main system memory in lieu of dedicated graphics RAM, reducing the amount of memory available to the operating system. They lack the extra memory necessary for sophisticated gaming, so they aren't usually suitable for playing any but the simplest games.
TV tuner: If you want to play and/or record live TV on your PC, you'll need a graphics board with a TV tuner. Several midrange and power boards with such tuners are available.

Overclocking: Running a graphics processor faster than the manufacturer's specified speed is popular among PC tweakers and dedicated gamers. While it carries risks such as overheating, when done within vendor-specified safety limits, it's a viable way of eking extra performance out of a midrange or power board.Be sure to read the manufacturer's recommendations and instructions before overclocking.
Quad SLI: nVidia's Quad SLI technology lets you combine four graphics chips in one PC. Quad SLI will let you play games at massive resolutions such as 1920 by 1200 and 2560 by 1600; and it really shines when you turn on high-end antialiasing and anisotropic filtering settings.

SHOPPING TIPS
If you stick to what you need and follow these tips, you should be able to get a board at a price you can smile about.

Go for midrange boards: Unless you need the ultimate gaming board (and have a brand-new, high-end PC that can use it to maximum advantage), aim below the top. You can usually save at least $100, and you won't sacrifice much in terms of performance.

Gamers need more power: If you're planning to play new games, you'll want a powerful board that supports the DirectX 10 API and has 512MB of DDR SDRAM.

Check the connection: PCI Express cards can't fit in AGP slots and vice versa, so check what your PC can accommodate before you buy. Similarly, make sure there is room inside your PC for a board that takes up two slots.

Consider your needs: Don't throw away money on features you won't be using. Unless you're planning to capture and edit digital video, for example, get a board without video- and audio-in ports. By getting only what you need, you can save money or spend the money on features (such as more RAM) that matter more to you.

Determine your budget: Before you go for buying a graphics card, determine your budget, your requirement for graphics card as well as how will you be using it. Doing so will save you from spending more than what you required.

So while you go about buying the best graphics card I will take your leave and will post a new topic soon. Stay Tune for more.
I hope you enjoyed the post about graphics card, Any comment or views are welcome. If you have any questions about which graphics card to buy or would like to suggest few graphics card for other users, you are most welcome to do so.

What is Motherboard

Hi Friends,
How are you all,

I hope you enjoyed reading details about processors. Today I am gonna elaborate about one of the most vital components of CPU that is MOTHERBOARD.

In today's article I will try to explain you brief of what motherboard is and other details about motherboard and also helping you select the best suitable to you?

What is motherboard??

A motherboard is the central or primary circuit board making up a complex electronic system, such as a modern computer. It is also known as a mainboard, baseboard, system board, planar board or, on Apple computers, a logic board, and is sometimes abbreviated as mobo.

The motherboard of a typical desktop consists of a large printed circuit board. It holds electronic components and interconnects, as well as physical connectors. It often consists of two components or chips known as the Northbridge and Southbridge, though they may also be integrated into a single component. These chips determine, to an extent, the features and capabilities of the motherboard.

Most motherboards include, at a minimum:

sockets (or slots) in which one or more microprocessors are installed.
slots into which the system's main memory is installed (typically in the form of DIMM modules containing DRAM chips)
a Chipset which forms an interface between the CPU's front-side bus, main memory, and peripheral buses
Non volatile chips (usually Flash ROM in modern motherboards) containing the system's firmware and BIOS
a clock generator which produces the system clock signal to synchronize the various components
slots for expansion cards (these interface to the system via the buses supported by the chipset)
power connectors and circuits, which receive electrical power from the computer power supply and distribute it to the CPU, chipset, main memory, and expansion cards.
Additionally, nearly all motherboards include logic and connectors to support commonly-used input devices, such as PS 2 connectors for a mouse and keyboard.

There are a lot of motherboards on the market to choose from. The big question is, how do you go about choosing which one is right for you?

The first factor to think about concerning motherboards is the size, or form factor. The most popular motherboard form factor today is ATX, which evolved from it's predecessor, the Baby AT, a smaller version of the AT (Advanced Technology) form factor.

The important differential is which CPU the board supports. Two of the biggest makes of CPUs at the moment are Intel and AMD, yet you cannot buy motherboards that support the use of either: it will support one or the other, due to physical differences in the connectors. Furthermore, you must choose a specific type of processor; for example, an AMD Athlon 64 or or Intel Core 2 Duo.

Chipsets are a crucial part of a motherboard, a chipset supports the facilities offered by the processor. A chipset is part of the motherboard, and cannot be upgraded without upgrading the whole board. There are a few main producers of chipsets, which are AMD, Intel, NVidia and Via: The latter two make chipsets for both AMD and Intel processors; AMD and Intel only make chipsets compatible with their own processors.


The next thing is how much RAM you want. RAM, or Random Access Memory, is the main memory in a computer, and is used mainly to store information that is being actively used or that changes often. It is always wise to choose a motherboard that can support more RAM than you currently need. For example, if you want 512MB of RAM in your computer, it would be wise to buy a motherboard that supports at least 1GB of RAM (many now support 4GB). This is simply to help make your computer ‘future proof': if you need to upgrade your memory, you will not need to upgrade your motherboard too.

You are likely to want various expansion cards (such as graphics cards, sound cards and so on). These components tend to have physically different connectors. The PCI-E slot is the most common graphics card interface nowadays, but the AGP slot is still in use.

Aside from the main differences I have covered, there a few more details to consider. All motherboards have USB sockets for peripheral devices. You also need to ensure that your motherboard has the right socket for your drives (hard drive, CD ROM drive, etc), which are generally SATA and IDE.

Unless you have limitless resources, price is always a consideration when buying computer component. A motherboard usually takes up a fairly large part of any PC budget, so it requires careful consideration. A cheap motherboard may be more unreliable and more trouble than it is worth. A motherboard is one of those components where it pays to spend a little extra.

Finally, try to buy from a reputable retailer: It is always worth doing so just in case you have any problems.

That's it for today, I hope you got a brief idea about how you should go about buying a motherboard and a CPU.

Please feel free to comment or write views on the above article. It will help me do better.

Image of Motherboard will be uploaded soon