SAVE EARTH

Difference between Static RAM and Dynamic RAM

Your computer probably uses both static RAM and dynamic RAM at the same time, but it uses them for different reasons because of the cost difference between the two types. If you understand how dynamic RAM and static RAM chips work inside, it is easy to see why the cost difference is there and you can also understand the names.
Dynamic RAM is the most common type of memory in use today. Inside a dynamic RAM chip, each memory cell holds one bit of information and is made up of two parts: a transistor and a capacitor. These are, of course, extremely small transistors and capacitors so that millions of them can fit on a single memory chip. The capacitor holds the bit of information -- a 0 or a 1. The transistor acts as a switch that lets the control circuitry on the memory chip read the capacitor or change its state.

A capacitor is like a small bucket that is able to store electrons. To store a 1 in the memory cell, the bucket is filled with electrons. To store a 0, it is emptied. The problem with the capacitor's bucket is that it has a leak. In a matter of a few milliseconds a full bucket becomes empty. Therefore, for dynamic memory to work, either the CPU or the memory controller has to come along and recharge all of the capacitors holding a 1 before they discharge. To do this, the memory controller reads the memory and then writes it right back. This refresh operation happens automatically thousands of times per second.

This refresh operation is where dynamic RAM gets its name. Dynamic RAM has to be dynamically refreshed all of the time or it forgets what it is holding. The downside of all of this refreshing is that it takes time and slows down the memory.

Static RAM uses a completely different technology. In static RAM, a form of flip-flop holds each bit of memory . A flip-flop for a memory cell takes 4 or 6 transistors along with some wiring, but never has to be refreshed. This makes static RAM significantly faster than dynamic RAM. However, because it has more parts, a static memory cell takes a lot more space on a chip than a dynamic memory cell. Therefore you get less memory per chip, and that makes static RAM a lot more expensive.
So static RAM is fast and expensive, and dynamic RAM is less expensive and slower. Therefore static RAM is used to create the CPU's speed-sensitive cache, while dynamic RAM forms the larger system RAM space.

Windows 7

Windows 7 is, as of March 2010, the latest version of Microsoft Windows, a series of operating systems produced by Microsoft for use on personal computers, including home and business desktops, laptops, netbooks, tablet PCs, and media center PCs.Windows 7 was released to manufacturing on July 22, 2009, and reached general retail availability on October 22, 2009, less than three years after the release of its predecessor, Windows Vista. Windows 7's server counterpart, Windows Server 2008 R2, was released at the same time.
Unlike its predecessor, which introduced a large number of new features, Windows 7 was intended to be a more focused, incremental upgrade to the Windows line, with the goal of being fully compatible with applications and hardware with which Windows Vista is already compatible. Presentations given by Microsoft in 2008 focused on multi-touch support, a redesigned Windows Shell with a new taskbar, referred to as the Superbar, a home networking system called HomeGroup, and performance improvements. Some applications that have been included with prior releases of Microsoft Windows, including Windows Calendar, Windows Mail, Windows Movie Maker, and Windows Photo Gallery, are not included in Windows 7; most are instead offered separately as part of the free Windows Live Essentials suite.

Software Engineering

Software engineering
Software engineering is the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software, and the study of these approaches; that is, the application of engineering to software.
The term software engineering first appeared in the 1968 NATO Software Engineering Conference and was meant to provoke thought regarding the current "software crisis" at the time. Since then, it has continued as a profession and field of study dedicated to designing, implementing, and improving software that is of higher quality, more affordable, maintainable, and quicker to build. Since the field is still relatively young compared to its sister fields of engineering, there is still much debate around what software engineering actually is, and if it conforms to the classical definition of engineering. It has grown organically out of the limitations of viewing software as just computer programming.

Typing Etiquettes

Positioning the Keyboard
• The keyboard should be placed directly in front of the body to avoid twisting the neck and torso.
• The keyboard should be positioned in front of the computer monitor with the letters G & H approximately in line with your navel. This is particularly good positioning when doing a lot of keyboard work.
• The keyboard should be positioned according to the distance the forearms extend from the neutral position of the elbows by the side of the body.
Keyboard Height and Slope
• Arms should be parallel to the floor when placed gently on the keyboard. The seated elbow height should be a little higher than the height of the keyboard. Raise or lower the office chair to achieve this position.
• The slope of the keyboard should be as close to the flat position as possible. It is largely determined by what feels comfortable; however there should be a good straight alignment across the forearms, wrists and hands.
Providing a keyboard without a numeric pad can reduce the keyboard width and allow the mouse to be operated closer to the user.
Using a Keyboard Platform
• If a keyboard platform is used it should be large enough to accommodate both the keyboard and mouse on the same level.
• If the keyboard platform is not large enough the mouse tends to be placed on the desktop that is higher and further away. This will lead to excessive reaching while trying to operate the mouse.
Do Not Anchor the Wrists
• When typing, it is advisable to not anchor (rest) the wrists on the desk or a wrist rest. Resting the wrists while typing may be harmful because it encourages bending and holding static postures. It can also apply pressure to the underside of the wrists.
• A wrist rest is designed to provide support during pauses, when not typing (such as when reading from the screen). If using a wrist rest ensure that it is the same height as the front edge of the keyboard.
• Where possible, the feet at the rear of the keyboard should be kept in a lowered position to minimise the height and angle of the keyboard.

ENCRYPTION

ENCRYPTION

In cryptography, encryption is the process of transforming information (referred to as plaintext) using an algorithm (called cipher) to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information (in cryptography, referred to as ciphertext). In many contexts, the word encryption also implicitly refers to the reverse process, decryption (e.g. “software for encryption” can typically also perform decryption), to make the encrypted information readable again (i.e. to make it unencrypted).
Encryption has long been used by militaries and governments to facilitate secret communication. Encryption is now commonly used in protecting information within many kinds of civilian systems. For example, the Computer Security Institute reported that in 2007, 71% of companies surveyed utilized encryption for some of their data in transit, and 53% utilized encryption for some of their data in storage.[1] Encryption can be used to protect data "at rest", such as files on computers and storage devices (e.g. USB flash drives). In recent years there have been numerous reports of confidential data such as customers' personal records being exposed through loss or theft of laptops or backup drives. Encrypting such files at rest helps protect them should physical security measures fail. Digital rights management systems which prevent unauthorized use or reproduction of copyrighted material and protect software against reverse engineering (see also copy protection) are another somewhat different example of using encryption on data at rest.
Encryption is also used to protect data in transit, for example data being transferred via networks (e.g. the Internet, e-commerce), mobile telephones, wireless microphones, wireless intercom systems, Bluetooth devices and bank automatic teller machines. There have been numerous reports of data in transit being intercepted in recent years.[2] Encrypting data in transit also helps to secure it as it is often difficult to physically secure all access to networks.
Encryption, by itself, can protect the confidentiality of messages, but other techniques are still needed to protect the integrity and authenticity of a message; for example, verification of a message authentication code (MAC) or a digital signature. Standards and cryptographic software and hardware to perform encryption are widely available, but successfully using encryption to ensure security may be a challenging problem. A single slip-up in system design or execution can allow successful attacks. Sometimes an adversary can obtain unencrypted information without directly undoing the encryption. There are a number of reasons why an encryption product may not be suitable in all cases. First, e-mail must be digitally signed at the point it was created to provide non-repudiation for some legal purposes, otherwise the sender could argue that it was tampered with after it left their computer but before it was encrypted at a gateway. An encryption product may also not be practical when mobile users need to send e-mail from outside the corporate network.

Why You Need To Update Your Computer Device Drivers?

Some people don’t have the habit of updating their computer drivers regularly. Actually, like Windows updates, it is necessary for you to update device drivers periodically. Because they are also important parts of a Windows system and have a great effect on PC performance.

What is Device Driver?

Device driver is a special system program which allows Windows system to connect with the device on a computer. Only with it, can Windows system give orders to a device and make the device implement operations. Without a driver, you will not be able to use your printer, camera, scanner or other hardware on your PC. You can see how important it is.

Why Need to Update Computer Drivers?

A lot of hardware manufacturers release updates of drivers for their products frequently for the purpose of fixing some bugs or improving the performance of the hardware. Some drivers, like software, have bugs or errors more or less. And some cannot make the most of devices and even prevent the hardware from achieving high performance.

And driver files are easily corrupted or deleted by some invalid operation by you or virus. When one of them is corrupt or missing, the device will not be able to work properly. In such a situation, you will need to reinstall the driver to make the device work properly.

How to Update Device Drivers?

You can go to the websites of the manufacturers to check if there are any updates and download the latest version. Please note that for a specific hardware model there can be several versions for different Windows systems! You need to make sure the driver you download is for the model of your device and the Windows system that you are using. If you install a wrong one, not only will the device not be able to work properly but also your system can crash down.

Computer Safety Tips

Computer Safety Tips
Achieving good computer security can seem like a daunting task. Fortunately, following the few simple steps outlined below can provide a good measure of security in very little time.
• Use antivirus software and keep it updated. You should check for new definition updates daily. Most antivirus software can be configured to do this automatically.
• Install security patches. Vulnerabilities in software are constantly being discovered and they don't discriminate by vendor or platform. It's not simply a matter of updating Windows; at least monthly, check for and apply updates for all software you use.
• Use a firewall. No Internet connection is safe without one. Firewalls are necessary even if you have a dial-up Internet connection - it takes only minutes for a non-fire walled computer to be infected.
• Secure your browser. Many labor under the dangerous misconception that only Internet Explorer is a problem. It's not the browser you need to be concerned about. Nor is it a matter of simply avoiding certain 'types' of sites. Known, legitimate websites are frequently being compromised and implanted with malicious javascript that foists malware onto visitors' computers. To ensure optimum browsing safety, the best tip is to disable javascript for all but the most essential of sites - such as your banking or regular ecommerce sites. Not only will you enjoy safer browsing, you'll be able to eliminate unwanted pop-ups as well.
• Take control of your email. Avoid opening email attachments received unexpectedly - no matter who appears to have sent it. Remember that most worms and trojan-laden spam try to spoof the sender's name. And make sure your email client isn't leaving you open to infection. Reading email in plain text offers important security benefits that more than offset the loss of pretty colored fonts.
• Treat IM suspiciously. Instant Messaging is a frequent target of worms and trojans. Treat it just as you would email.
• Avoid P2P and distributed file sharing. Torrent, Kazaa, Gnutella, Morpheus and at least a dozen other file sharing networks exist. Most are free. And all are rife with trojans, viruses, worms, adware, spy ware, and every other form of malicious code imaginable. There's no such thing as safe anonymous file sharing. Avoid it like the plague.
• Keep abreast of Internet scams. Criminals think of clever ways to separate you from your hard earned cash. Don't get fooled by emails telling sad stories, or making unsolicited job offers, or promising lotto winnings. Likewise, beware of email masquerading as a security concern from your bank or other eCommerce site.
• Don't fall victim to virus hoaxes. Dire sounding email spreading FUD about non-existent threats serve only to spread needless alarm and may even cause you to delete perfectly legitimate files in response.
Remember, there's far more good than bad on the Internet. The goal isn't to be paranoid. The goal is to be cautious, aware, and even suspicious. By following the tips above and becoming actively engaged in your own security, you'll not only be protecting yourself, you'll be contributing to the protection and betterment of the Internet as a whole.