Ajax Programming

Brief history
Ajax is only a name given to a set of tools that were previously existing.
The main part is XMLHttpRequest, a class usable in JavaScript , that was implemented into Internet Explorer since the 4.0 version.
The same concept was named XMLHTTP some times, before the Ajax name becomes commonly used.
The use of XMLHttpRequest in 2005 by Google, in Gmail and GoogleMaps has contributed to the success of this format. But this is the name Ajax itself that made the technology so popular.

Why to use Ajax?
Mainly to build a fast, dynamic website, but also to save resources.
For improving sharing of resources, it is better to use the power of all the client computers rather than just an unique server and network. Ajax allows to perform processing on client computer (in JavaScript) with data taken from the server.
The processing of web page formerly was only server-side, using web services or PHP scripts, before the whole page was sent within the network.
But Ajax can selectively modify a part of a page displayed by the browser, and update it without the need to reload the whole document with all images, menus, etc...
For example, fields of forms, choices of user, may be processed and the result displayed immediately into the same page.

What is Ajax in depth?
Ajax is a set of technologies, supported by a web browser, including these elements:
HTML and CSS for presenting.
JavaScript (ECMAScript) for local processing, and DOM (Document Object Model) to access data inside the page or to access elements of XML file read on the server (with the getElementByTagName method for example)...
The XMLHttpRequest class read or send data on the server asynchronously.
optionally...
The DomParser class may be used
PHP or another scripting language may be used on the server.
XML and XSLT to process the data if returned in XML form.
SOAP may be used to dialog with the server.

The "Asynchronous" word, means that the response of the server while be processed when available, without to wait and to freeze the display of the page.

How does it works?
Ajax uses a programming model with display and events. These events are user actions, they call functions associated to elements of the web page.
Interactivity is achieved with forms and buttons. DOM allows to link elements of the page with actions and also to extract data from XML files provided by the server.
To get data on the server, XMLHttpRequest provides two methods:
- open: create a connection.
- send: send a request to the server.
Data furnished by the server will be found in the attributes of the XMLHttpRequest object:
- responseXml for an XML file or
- responseText for a plain text.

Take note that a new XMLHttpRequest object has to be created for each new file to load.

We have to wait for the data to be available to process it, and in this purpose, the state of availability of data is given by the readyState attribute of XMLHttpRequest.

States of readyState follow (only the last one is really useful):
0: not initialized.
1: connection established.
2: request received.
3: answer in process.
4: finished.

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Sport : Liverpool

Liverpool is associated with a variety of sports, most notably football, but also a number of others.

Liverpool has two Premier League football clubs: Everton F.C. at Goodison Park and Liverpool F.C. at Anfield. Liverpool are statistically the most successful English football club of all-time, having won the league title 18 times, FA Cup seven times, Football League Cup seven times, European Cup/UEFA Champions League five times and UEFA Cup three times. Everton have also enjoyed spells of dominance, having won the league title nine times, FA Cup five times, and the European Cup Winners' Cup once. Their most recent success was the FA Cup in 1995. South Liverpool F.C. were once another successful professional side, however they have experienced a turbulent history and are currently in the Liverpool County Premier League.

Liverpool is the only city to have staged top division football every season since the formation of the Football League in 1888, and both Liverpool and Everton have played in the top division every season since 1962.

Professional basketball is played in the city with the addition of Everton Tigers into the elite British Basketball League in 2007. The club is associated with Everton Football Club, and is part of the Toxteth Tigers youth development programme, which reaches over 1,500 young people every year.[25] The Tigers will commence play in Britain's top league for the 2007-08 season, though their home venue has yet to be confirmed. Their closest professional rivals are the Chester Jets, based 18 miles away in Chester.

County cricket is occasionally played in Liverpool, with Lancashire County Cricket Club typically playing one match every year at Liverpool Cricket Club, Aigburth.

Aintree Racecourse to the north of Liverpool in the adjacent borough of Sefton is home to the famous steeplechase, the Grand National, One of the most famous events in the international horse racing calendar, it is held in early April each year. In addition to horse-racing, Aintree has also hosted motor racing, including the British Grand Prix in the 1950s and 1960s.

Speedway racing was formerly staged at Stanley Stadium in Prescot Road from the 1920s until the late 1930s. It then reopened in 1949, with the Liverpool Chads taking part in the National League, until the track closed mid-season in 1953. A brief open season in 1959 was followed by the final season in 1960 when the Liverpool Pirates participated in the Provincial League. Peter Craven, the World Champion in 1955 and 1962, started out at Stanley Stadium before moving on to Belle Vue in Manchester.

A speedway track also operated in the mid-1930s at Seaforth Stadium.

Liverpool Harriers, who meet at Wavertree Athletics Centre, are one of five athletic clubs. Liverpool has a long history of boxing that has produced John Conteh, Alan Rudkin and Paul Hodkinson and hosts high level amateur boxing events. Park Road Gymnastics Centre provides training to a high level. The City of Liverpool Swimming Club has been National Speedo League Champions 8 out of the last 11 years. Liverpool Tennis Development Programme based at Wavertree Tennis Centre is one of the largest in the UK.[26] Liverpool is also home to the Red Triangle Karate Club, which provided many of the 1990 squad that won the World Shotokan Championships in Sunderland. Luminaries include Sensei Keinosuke Enoeda, Sensei Frank Brennan, Sensei Omry Weiss, Sensei Dekel Kerer, Sensei Andy Sherry and Sensei Terry O'Neill, who is also famous for various acting roles.

Rugby league is played at amateur and student level within the city; the last professional team bearing the city's name was Liverpool City, which folded in the 1960s. Liverpool St Helens F.C. is one of the oldest rugby union teams in the UK.

Liverpool is one of three cities which still host the traditional sport of British Baseball and it hosts the annual England-Wales international match every two years, alternating with Cardiff and Newport. Liverpool Trojans are the oldest existing baseball club in the UK.

The Royal Liverpool Golf Club, situated in the nearby town of Hoylake on the Wirral Peninsula, has hosted The Open Championship on a number of occasions, most recently in 2006. It has also hosted the Walker Cup.

Liverpool has a Lacrosse Club, open to both Men and Women. Playing at Liverpool Cricket Club in Aigburth, South Liverpool, the Mens team is mainly built around the University squad, but with University old boys and locals joining the team. Having started in the lowest division in the north, Division 5, they have successfully gained promotion to Division 4 in their first competitive season.

Parkour/freerunning is a popular sport in liverpool. Two well-known traceurs from the city are Daniel Ilabaca and Ryan Doyle.

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News : Global Warming

Global warming is the increase in the average temperature of the Earth's near-surface air and oceans since the mid-twentieth century, and its projected continuation.

The average global air temperature near the Earth's surface increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the hundred years ending in 2005. The Intergovernmental Panel on Climate Change (IPCC) concludes "most of the observed increase in globally averaged temperatures since the mid-twentieth century is very likely due to the observed increase in anthropogenic (man-made) greenhouse gas concentrations" via an enhanced greenhouse effect. Natural phenomena such as solar variation combined with volcanoes probably had a small warming effect from pre-industrial times to 1950 and a small cooling effect from 1950 onward.

These basic conclusions have been endorsed by at least thirty scientific societies and academies of science, including all of the national academies of science of the major industrialized countries. While individual scientists have voiced disagreement with some findings of the IPCC, the overwhelming majority of scientists working on climate change agree with the IPCC's main conclusions.

Climate model projections summarized by the IPCC indicate that average global surface temperature will likely rise a further 1.1 to 6.4 °C (2.0 to 11.5 °F) during the twenty-first century. This range of values results from the use of differing scenarios of future greenhouse gas emissions as well as models with differing climate sensitivity. Although most studies focus on the period up to 2100, warming and sea level rise are expected to continue for more than a thousand years even if greenhouse gas levels are stabilized. The delay in reaching equilibrium is a result of the large heat capacity of the oceans.

Increasing global temperature will cause sea level to rise, and is expected to increase the intensity of extreme weather events and to change the amount and pattern of precipitation. Other effects of global warming include changes in agricultural yields, trade routes, glacier retreat, species extinctions and increases in the ranges of disease vectors.

Remaining scientific uncertainties include the amount of warming expected in the future, and how warming and related changes will vary from region to region around the globe. Most national governments have signed and ratified the Kyoto Protocol aimed at reducing greenhouse gas emissions, but there is ongoing political and public debate worldwide regarding what, if any, action should be taken to reduce or reverse future warming or to adapt to its expected consequences.

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Windows Vista

Windows Vista (pronounced /ˈvɪstə/) is a line of operating systems developed by Microsoft for use on personal computers, including home and business desktops, laptops, Tablet PCs, and media center PCs. Prior to its announcement on July 22, 2005, Windows Vista was known by its codename "Longhorn". Development was completed on November 8, 2006; over the following three months it was released in stages to computer hardware and software manufacturers, business customers, and retail channels. On January 30, 2007, it was released worldwide, and was made available for purchase and download from Microsoft's website. The release of Windows Vista comes more than five years after the introduction of its predecessor, Windows XP, the longest time span between successive releases of Microsoft Windows.

Windows Vista contains many changes and new features, including an updated graphical user interface and visual style dubbed Windows Aero, improved searching features, new multimedia creation tools such as Windows DVD Maker, and redesigned networking, audio, print, and display sub-systems. Vista also aims to increase the level of communication between machines on a home network, using peer-to-peer technology to simplify sharing files and digital media between computers and devices. Windows Vista includes version 3.0 of the .NET Framework, which aims to make it significantly easier for software developers to write applications than with the traditional Windows API.

Microsoft's primary stated objective with Windows Vista, however, has been to improve the state of security in the Windows operating system. One common criticism of Windows XP and its predecessors has been their commonly exploited security vulnerabilities and overall susceptibility to malware, viruses and buffer overflows. In light of this, Microsoft chairman Bill Gates announced in early 2002 a company-wide "Trustworthy Computing initiative" which aims to incorporate security work into every aspect of software development at the company. Microsoft stated that it prioritized improving the security of Windows XP and Windows Server 2003 above finishing Windows Vista, thus delaying its completion.

While these new features and security improvements have garnered positive reviews, Vista has also been the target of much criticism and negative press. Criticism of Windows Vista has targeted high system requirements, its more restrictive licensing terms, the inclusion of a number of new digital rights management technologies aimed at restricting the copying of protected digital media, lack of compatibility with certain pre-Vista hardware and software, and the number of authorization prompts for User Account Control. As a result of these and other issues, Vista has seen adoption and satisfaction rates lower than Windows XP.

Read More - Windows Vista