HTML has a fixed set of element types, for example TITLE, H1, H2, EM, BODY, P, HR, and so on. A valid HTML document must use these elements.

A valid URL may start with "http://" or "www" or just the domain name (i.e., "about-the-web.com").

It provides a means of checking that the addresses you have entered are in the correct format. It does not check to see if the address is a valid one.

Client-side scripts cannot be used to interact with a remote database, but are often used to validate user inputs entered on HTML forms that are submitted for processing by a server-side program.

Do the Final Steps. Validate Your Code

To validate files, Office File Validation compares a file’s structure to a predefined file schema, which is a set of rules that determine what a readable file looks like.

You can run your coded files through one of several on-line HTML validation services that will tell you if your code conforms to accepted HTML.

Every time that a file fails validation, Office 2010 collects information about why the file failed validation.

A validation rule represents one kind of requirement that your diagram should follow.

A "normal variable" is a location in memory that can hold a value.

Then, somewhere in the while statement there is an increment step that increases the value of y.

The four bytes at that address are known to you, the programmer, as i, and the four bytes can hold one integer value.

All programs use variables to hold pieces of data temporarily.

XML entities are a bit like variables in other programming languages - they're XML constructs which are referenced by a name and store text, images and file references.

Variables must be defined (or declared) in a program before you can use them, and you must give each variable a specific type.

Most operating systems, drivers and utility programs are written by commercial organizations that distribute executable versions of their software -- versions that can't be studied or altered.

Each new version of Windows raises the specification of the PC needed to run it.

The version of POSIX threads distributed with most flavors of Linux was developed by Xavier Leroy.

Most email applications can be configured to view a received file using a 'viewer'.

Windows Explorer is a program which allows you to view all of your folders, and the files that belong in those folders.

As another example of the power of ActiveX, this technology can allow you to view and edit PowerPoint presentations directly within your Web browser.

NOTE: To make a hidden folder viewable, perform the following steps:

Note that these trace files are transportable and viewable on machines other than where they were generated.

Comments in HTML are like comments in a computer program--the text you enter is not used by the browser in any formatting and is not directly viewable by the reader just as computer program comments are not used and are not viewable.

The latest versions of the Acrobat Reader allow for the viewing of documents within the browser window.

In this chapter we explored the issues of download files and explained how to save webpages to your local disk for off-line viewing.

The settings option is used to change the viewing area of the desktop, setting font size, and size of the desktop area.

Because storage space on a hard disk is so cheap and plentiful, it forms the final stage of a CPUs memory hierarchy, called virtual memory.

Putting a host to be your virtual IP makes it act as the front for your real host, and the firewall will forward all packets through the virtual host to the real host.

See your computer uses virtual (as in not physical) ports to communicate with the outside world.

People sometimes referred to them as specialty databases, subject-specific databases, virtual libraries, and other similar terms.

Additionally, some CGI scripts record the information input by the visitor (for example, scripts to allow on-line shopping may record the contents of the current visitor's virtual shopping basket) in temporary files.

From a security point of view, the Internet is a vast, virtual ecosystem filled with predators and parasites as well as "prey" and "hosts," much as we find in any biological system.

A virus is a program designed by a computer programmer (malicious hacker) to do a certain unwanted function.

Computer viruses are malicious programs that, like their biological namesakes, spread from one host to the next, doing damage as they go.

People create viruses. A person has to write the code, test it to make sure it spreads properly and then release the virus.

The idea behind a meta search engine is that an Internet user should be able to visit one site, conduct a search, and view the results from multiple search engines on a single results page.

Before you start the install, visit the Website of the Linux distribution you have opted for and check out on the hardware compatibility documents.

After that, visit each manufacturer's web site to make sure that W2K drivers are available.

The cache directory is used by the browser to speed loading of the web sites if you make a return visit, but you are not assured that the files will be safe there as the browsers periodically clean out the cache directory to prevent it from growing too large.

A picture is worth a thousand words and a second visit to a website.

Sound files may be incorporated into Web sites, and are also available for downloading independent of Web site visits.

This allows the appearance or behaviour of the website to be customised for that visitor.

By a search query we mean the keyword or keyword phrase the visitor enters into the search form of the search engine.

When web pages or HTML documents are viewed by a visitor or client the web browser will formatted the document using the codes or markup tags and display it on the screen.

Memory can be split into two main categories: volatile and nonvolatile.

The key difference between the hard disk and the RAM is that RAM is 'volatile' - that is, its contents are lost when you turn the computer off.

Many of the advanced systems employ a series of caches to reduce the number of slow mechanical "seeks" of the disk drive heads, instead reading directly from volatile memory at bus speeds.

This is crucial for keeping large volumes of data from clogging the connections of "innocent bystanders."

Initially, the scale of the distributed backup dilemma, with the volume of data and the demand for location-transparent access, seems to point to an IS-centric solution because of the size and experience of traditional data center resources.

Use a volume manager or adaptive RAID technology to load balance different database activities.

Do you want one large partition for the entire drive? Or do you want to separate it into different drive volumes?

If you created additional partitions on this drive, format those volumes now.

In addition, if your operating system supports partitions or volumes (i.e., separately mounted file systems with independent attributes) consider partitioning your file system so as to separate critical functions from other activity.

Attackers can use this vulnerability in SNMP to reconfigure or shut down devices remotely.

Unlike the Y2K bug, which threatens to cripple computers unable to distinguish years written in two-digit shorthand, this vulnerability opens computers to attacks by malicious hackers, who can use the bug to commandeer the targeted computer.

Another vulnerability is widely thought to be the means used to compromise more than 30,000 Linux systems.

A recent survey by the CERT/CC shows that over 80% of the TLD domains are running on servers that are potentially vulnerable to this form of attack.

Setting either of these policy settings leaves the computer highly vulnerable, potentially allowing an attacker to run malicious code on the computer.

We also see intruders remotely execute packet flooding attacks from Microsoft Internet Information Server (IIS) systems using lists of hosts that are vulnerable and will allow remote HTTP requests to execute arbitrary commands.