Hard drives do fail, of course, but this is sufficiently rare to make it a non-issue for some people and besides, the chances of losing data stored on your PC's hard drive at the same time as that on an external hard drive are slim indeed.

There are multiple DNS servers at every level, so that if one fails, there are others to handle the requests.

Unfortunately, Windows XP doesn't allow you to use the disk-checking utility ScanDisk on demand. If you're worried that a drive may be about to fail, right-click its icon.

If an innocent user makes normal page requests during a attack, the requests may fail completely, or the pages may download so slowly as to make the website unusable.

If those numbers were to be corrupted, network communications would fail.

Indeed, the bulk of the book is devoted to the presentation of techniques and tools that assist testers as they try to make the application fail by feeding it various types of inputs (hence the term fault injection).

This does happen, but not often - new drives have a life span, or 'mean time before failure' (MTBF) of as much as a million hours.

Consider security, packet loss, hardware failure, network congestion, and data corruption.

Incompatibility between components can lead to difficulties, as can a failure of components - though the latter is, thankfully, a rare occurrence.

Find and read the FAQ, so that you don't post a question that has already been answered.

A FAQ that answers users' questions, but not a lot of serious help files.

We feel this topic is too sensitive to address in a FAQ, however, an independently maintained list (no warranty or recommendations are implied) can be found online.

Though many fields only allow a single line of input some allow multiple lines.

You will be presented with a simple dialog box with a Server/IP address field and another field for the port ID.

Okay, so you'll probably have some kind of form validation implemented to prevent fields in your forms being left blank,

Each piece of information about that person or record are stored in Fields. All the information in all the records makes up the Database.

In the above example we have used XML to describe data, and we've used tag names that represent field names of the data.

If you are using XML it is possible that some fields might contain no data. In that case the tags would be empty.

With all your important files saved on a removable disc such as a floppy or CD, you'll be able to continue your work on another PC.

Here is a quick view of some the files and folders that should be created on our Web server.

By contrast, dictation software recognizes your speech as incoming words to be inserted into a file as text.

A practice ((clogging inboxes with PDF files)) that is annoying not only because it can bypass most filters, but because it also adds to the already ballooning size of message stores.

The best use a combination of strategies, including filters based on words and phrases commonly found in spam messages, white and black lists to identify good and bad senders, reference to online databases of known spammers and Bayesian analysis - an examination of email messages to learn by example what constitutes spam.

Currently, the best method is to install a filtering firewall that restricts the input to your external interface (known as an input filter) by not allowing a packet through if it has a source address from your internal network.

Most ISPs provide software that will filter out the worst of this email.

If no virus is detected, the transfer proceeds; only files containing a virus are filtered.

Firewalls can filter packets at several different levels. They can look at IP addresses and block traffic coming from certain IP addresses or networks, check the TCP header and determine its state, and at higher levels they can look at the application or TCP/UDP port number.

Some search engines allow you to filter out pages that may lead to pornographic web sites or sites with content that might be considered offensive to some people.

Access lists are normally used to filter traffic at the packet level.

Use at least Cisco version 9.21 so you can filter incoming packets and check for address spoofing.

A firewall is really a group of programs, working from the gateway of your entire network.

Laptop anti-virus and personal firewalls help, but easily become outdated or disabled.

A firewall is simply a program or hardware device that filters the information coming through the Internet connection into your private network or computer system.

To enable our laptop to recognise hard disks over 65GB, we needed to install version 15 of the BIOS. We downloaded a small update from Dell's website. If we hadn't, the new one would have crashed the laptop, making it impossible to flash the BIOS.

If any of the problems outlined seem to fit your case, you should update or 'flash' the new BIOS. You'll find full instructions on how to do this on the manufacturer's Web site.

Luckily, you can update or 'flash' the BIOS, allowing it to recognise newly upgrade components.

More commonly known as Personal Digital Assistants (PDAs), palmtops are tightly integrated computers that often use flash memory instead of a hard drive for storage.

Hybrid technology may not be making an immediate splash, but adding flash memory to mechanical drives is an idea that's bound to pay benefits for mobile users.

Based on a type of ROM called electrically erasable programmable read-only memory (EEPROM), Flash memory provides fast, permanent storage.

Just as you'd organise pieces of paper on your desk into folders, Windows allows you to organise files on your PC by creating folders to put them in.

Your Internet connection is the slowest link in your computer. So your browser (Internet Explorer, Netscape, Opera, etc.) uses the hard disk to store HTML pages, putting them into a special folder on your disk.

Here is a quick view of some the files and folders that should be created on our Web server.

A font is the shape and size of a character of text. The three main types are serif (with tails); sans-serif (without tails); and script (similar to handwriting).

The most common adjustment to Web pages is to the fonts on the page. You can change the color, style, size, and face of your fonts, and you can do it all with CSS.

You probably already know that if the font specified isn't available on the client computer, the browser will use the default font (usually Times New Roman).

Now to format a disk left click on Format.

If you created additional partitions on this drive, format those volumes now. Type "format d:" or "format e:", where the letter corresponds to the volume you wish to format.

File System Configuration - this allows the user to add, format, check, and mount new storage devices.

Modern email programs provide the ability to allow users to format email messages with HTML and attach scripts to them for various purposes and it is possible for a malicious hacker to attempt to spread a virus by building a virus script into an HTML type of email message.

If the company wants to send e-mail across the Internet, it must format the message according to the Internet standard and must use standard Internet protocols to transfer the message.

If you will be dealing with clients and servers that use differing byte orders, then you will need to take care in how the data is formatted before sending with this function.

As with every multimedia format there are a number of types.

It's standard text, so can easily transfer from machine to machine. It's not in proprietary format, so anyone can read it, and if the tags are named sensibly, the XML is self-describing.

PNG is a graphics format specifically designed for use on the World Wide Web which enables compression of images without any loss of quality. Files using this format have a name ending with .PNG

Then there is the application layer, which is an HTTP header, telling the Web browser how to format a page.

Modern email programs provide the ability to allow users to format email messages with HTML and attach scripts to them for various purposes

HTML uses a set of standard codes to format text.

For the latter, a simple formatting of the hard disk, when the installation gets to that point, will do.

High level formatting is the act of structuring the partition for use by a file system supported by the operating system.

Groups often include discussion forums where users meet to solve each others' problems or share technical support experiences.

The Internet is home to a large community of individuals who carry out active discussions organized around topic-oriented forums distributed by e-mail.

Unlike forums, the other type of bulletin board available on the internet, a newsgroup isn't run from a single location.

The email goes on to ask you to forward this email to as many people as possible.

Similarly, the application gateway accepts all incoming e-mail, reformats it to use the proprietary system, and forwards each message to the appropriate recipient using the proprietary e-mail system.

One in six (about 15 percent) told Pew that private communications—IM logs, e-mails, or text messages—had been posted publicly by someone else or forwarded around.

The nodes communicate in short messages called frames, which are variably sized chunks of information.

On your packet-switched Ethernet, each packet of data can be considered a frame.

The term "frame" refers to the packets that are defined by hardware (i.e., layers 1-2). Thus, it is correct (and more precise) to refer to the packets used on an Ethernet as "Ethernet frames", ((...))

We've rounded up a number of free or inexpensive anti-spam programs, and the good news is that we found them all to be highly effective.

Our favourite solution for simple backups relies on a USB flash drive and a free Microsoft program called SyncToy.

Linux is a free operating system and there's plenty of free software to go with it.

Freeware are programs that you can freely download and use pursuant to the program's agreement. Most of the time, you will be able to use the program for as long as you want.

The software to accomplish this is available on the Web, some of it commercial, some of it freeware.

If the software concerned is freeware or shareware, there may be little you can do but avoid using it.

From a developer's perspective, each platform defines a set of conversion functions that can be used by an application to handle the conversion transparently, so it is not necessary to understand the intricacies of integer storage on each platform.

Although the keyboard remains the sole data-entry device, you may issue spoken commands to open a file, launch macros and perform many other editing functions.

The descriptor for the new client socket is passed to the thread function.

Commercially available software programs combine these two functionalities into one software package as in the case of PartitionMagic which also includes the BootMagic software.

These offer the point-and-click, drag-and-drop functionality associated with other user-friendly environments (for example, Macintosh), but are extremely flexible and can take on a number of different looks and feels.

The X-fi XtremeGamer is the base in Creative's line-up that still supports all of the essential EAX functionality.

Star Office desktop tools and KDE (Kool Desktop Environment) make Linux a contender for the desktop market. I have been using Star Office for a few weeks and its ease of use, along with its functionality, have me convinced it's as good as the 'other' OS we know.

It needs to stick out a little so it will be flush with the bezel when you re-attach it. Also make sure it appears straight. While this doesn't really affect functionality, it's a matter of aesthetics.

Generally, the critical parts of the operating system are maintained in RAM as long as the computer is on. This allows the CPU to have immediate access to the operating system, which enhances the performance and functionality of the overall system.