Good Practice Guide for Developers of Cultural Heritage Web Services
Good Practice Guide for Developers of Cultural Heritage Web ServicesThis section was originally published as QA Focus Briefing papers.
The Web is changing. It is no longer a phenomenon but has integrated itself within our culture. However for those creating digital resources and Web services times are far from stable. A wide range of collaborative, Web-based applications continue to be developed, such as blogs, wikis, podcasting, social networking software, RSS feeds etc. The Semantic Web is still on the cards and now we have Web 2.0 which could be an opportunity for a more sharing, more participative Web. This section will outline some of the most useful emerging collaborative technologies and consider how they apply to those creating Cultural Heritage Web Services.
The term "Web 2.0" refers to what some see as a second phase of development of the Web including its architecture and its applications. As used by its proponents, the phrase refers to one or more of the following:
However, a consensus on its exact meaning has not yet been reached. Many find it easiest to define Web 2.0 by associating it with companies or products that embody its principles. Some of the more well known Web 2.0 entities are Google Maps, Flickr, del.icio.us, digg, and Technorati.
Many recently developed concepts and technologies are seen as contributing to Web 2.0, including Weblogs, Wikis, Podcasts, RSS feeds and other forms of many to many publishing; social software, Web APIs, Web standards, Ajax and others.
Proponents of the Web 2.0 concept say that it differs from early Web development, retroactively labelled Web 1.0, in that it is a move away from static Web sites, the use of search engines, and surfing from one Web site to the next, to a more dynamic and interactive Web. Others argue that the original and fundamental concepts of the Web are not actually being superseded. Sceptics argue that the term is little more than a buzzword, or that it means whatever its proponents want it to mean in order to convince their customers, investors and the media that they are creating something fundamentally new, rather than continuing to develop and use well-established technologies.
Web 1.0 often consisted of static HTML pages that were updated rarely, if at all. The success of the dot-com era depended on a more dynamic Web (sometimes labelled Web 1.5) where content management systems served dynamic HTML pages created on the fly from a content database that could more easily be changed. In both senses, so-called eyeballing was considered intrinsic to the Web experience, thus making page hits and visual aesthetics important factors.
Proponents of Web 2.0 believe that Web usage is increasingly oriented toward interaction and rudimentary social networks, which can serve content that exploits network effects with or without creating a visual, interactive Web page. In one view, Web 2.0 sites act more as points of presence, or user-dependent portals, than as traditional Web sites.
Perhaps Web content will become less under the control of specialised Web designers and closer to Tim Berners-Lee's original concept of the Web as a democratic, personal, and DIY medium of communication. Content is less likely to flow through email and more likely to be posted on a attractive Web page and distributed by RSS.
With its allusion to the version numbers that commonly designate software upgrades, Web 2.0 was a natural way to indicate an improved form of the World Wide Web, and the term has been in occasional use for a number of years. It was eventually popularised by O'Reilly Media and MediaLive International for a conference they hosted after Dale Dougherty mentioned it during a brainstorming session. Dougherty suggested that the Web was in a renaissance, with changing rules and evolving business models. The participants assembled examples - "DoubleClick was Web 1.0; Google AdSense is Web 2.0. Ofoto is Web 1.0; Flickr is Web 2.0." - rather than definitions.
In their first conference opening talk, O'Reilly and Battelle summarised key principles they believe characterise Web 2.0 applications: the Web as platform; data as the driving force; network effects created by an "architecture of participation"; innovation in assembly of systems and sites composed by pulling together features from distributed, independent developers (a kind of "open source" development); lightweight business models enabled by content and service syndication; the end of the software adoption cycle ("the perpetual beta"); software above the level of a single device, leveraging the power of "the Long Tail".
An earlier usage of the phrase Web 2.0 was as a synonym for "Semantic Web", and indeed, the two concepts complement each other. The combination of social networking systems such as FOAF and XFN with the development of tag-based folksonomies and delivered through Blogs and Wikis creates a natural basis for a semantic environment. Although the technologies and services that comprise Web 2.0 are less powerful than an internet in which the machines can understand and extract meaning, as proponents of the Semantic Web envision, Web 2.0 represents a step in its direction.
Advancing from the old HTML, the technology infrastructure of Web 2.0 is complex and evolving, it includes server software, content syndication, messaging protocols, standards-based browsers, and various client applications. (Non-standard browser plugins and enhancements are generally eschewed.) These differing but complementary approaches provide Web 2.0 with information storage, creation, and dissemination capabilities that go beyond what was formerly expected of Web sites.
A Web site could be said to be built using Web 2.0 technologies if it features a number of the following techniques:
Technical:
General:
The first and most important evolution towards Web 2.0 involves the syndication of Web site content, using standardised protocols which permit end-users to make use of a site's data in another context, ranging from another Web site, to a browser plugin, or a separate desktop application. Protocols which permit syndication include RSS, RDF (as in RSS 1.1), and Atom, all of which are flavours of XML. Specialised protocols such as FOAF and XFN (both for social networking) extend functionality of sites or permit end-users to interact without centralised Web sites.
Web communication protocols are a key element of the Web 2.0 infrastructure. Two major ones are REST and SOAP.
In both cases, access to the service is defined by an API. Often this API is specific to the server, but standard Web service APIs (for example, for posting to a blog) are also widely used. Most, but not all, communications with Web services involve some form of XML (Extensible Markup Language).
Recently, a concept known as Ajax has evolved that can improve the user experience in some browser-based Web applications. It involves a Web page requesting an update for some part of its content, and altering that part in the browser, without refreshing the whole page at the same time. There are proprietary implementations (as in Google Maps) and open forms that can utilise Web service APIs, syndication feeds, or even screen scraping.
Another relevant standard is WSDL (Web Services Description Language), which is the standard way of publishing a SOAP API.
Web 2.0 functionality builds on the existing Web server architecture, but puts much greater emphasis on back-end software. Syndication differs only nominally from dynamic content management publishing methods, but Web services typically require much more robust database and workflow support, and become very similar to the traditional intranet functionality of an application server.
Web 2.0 has created new online social networks amongst the general public. Some web sites run social software where people work together; others reproduce multiple RSS feeds on one page; others provide deep-linking between individual Web sites.
The syndication and messaging capabilities of Web 2.0 have created a tightly-woven social fabric not possible previously. The meaning of these changes, however, has pundits divided. Basically, ideological lines run thusly: Web 2.0 either empowers the individual and provides an outlet for the 'voice of the voiceless'; or it elevates the amateur to the detriment of professionalism, expertise and clarity.
RSS is increasingly being used to provide news services and for syndication of content. The document provides a brief description of RSS news feed technologies which can be used as part of an communications strategy by projects and within institutions. The document summarises the main challenges to be faced when considering deployment of news feeds.
News feeds are an example of automated syndication. News feed technologies allow information to be automatically provided and updated on Web sites, emailed to users, etc. As the name implies news feeds are normally used to provide news; however the technology can be used to syndicate a wide range of information.
The BBC ticker [1] is an example of a news feed application. A major limitation with this approach is that the ticker can only be used with information provided by the BBC.
The RSS standard was developed as an open standard for news syndication, allowing applications to display news supplied by any RSS provider.
RSS is a lightweight XML application (see RSS fragment). Ironically the RSS standard proved so popular that it led to two different approaches to its standardisation. So RSS now stands for RDF Site Summary and Really Simple Syndication (in addition to the original phrase Rich Site Summary).
<title>BBC News</title> <url>http://news.bbc.co.uk/nol/shared/img/bbc_news_120x60.gif</url> <link>http://news.bbc.co.uk/</link> <item> <title>Legal challenge to ban on hunting</title> <description>The Countryside Alliance prepares a legal challenge to Parliament Act ... </description> <link>http://news.bbc.co.uk/go/click/rss/0.91/public/-/1/hi/... </link>.
Figure 1: Example Of An RSS File
Despite this confusion, in practice many RSS viewers will display both versions of RSS (and the emerging new standard, Atom).
There are a large number of RSS reader software applications available [2] and several different models. RSSxpress [3] (illustrated below) is an example of a Web-based reader which embeds an RSS feed in a Web page.
In addition to these two approaches, RSS readers are available with an email-style approach for the Opera Web browser and Outlook and as extensions for Web browsers.
There are several approaches to the creation of RSS news feeds. Software such as RSSxpress can also be used to create and edit RSS files. In addition there are a number of dedicated RSS authoring tools, including standalone applications and browser extensions (see [9]). However a better approach may be to generate RSS and HTML files using a CMS or to transform between RSS and HTML using languages such as XSLT.
Issues which need to be addressed when considering use of RSS include:
Wiki technologies are increasingly being used to support development work across distributed teams. This document aims to give a brief description of Wikis and to summarise the main challenges to be faced when considering the deployment of Wiki technologies.
A Wiki or wiki (pronounced "wicky" or "weekee") is a Web site (or other hypertext document collection) that allows a user to add content. The term Wiki can also refer to the collaborative software used to create such a Web site [4].
The key characteristics of typical Wikis are:
Wikipedia is the largest and best-known Wiki - see <http://www.wikipedia.org/>.
Wikipedia provides a good example of a community Wiki in which content is provided by contributors around the world.
Wikipedia appears to have succeeded in providing an environment and culture which has minimised the dangers of misuse. Details of the approaches taken on the Wikipedia are given on the Wikipedia Web site [5].
Wikis can be used for a number of purposes:
Advantages of Wikis include:
Disadvantages of Wikis include:
A useful article on Making the Case for a Wiki is available in Ariadne [9].
A folksonomy is a decentralised, social approach to creating metadata for digital resources. It is usually created by a group of individuals, typically the resource users, who add natural language tags to online items, such as images, videos, bookmarks and text. These tags are then shared and sometimes refined. Folksonomies can be divided into broad folksonomies, when lots of users tag one object, and narrow folksonomies, when a small number of users tag individual items. This new social approach to creating online metadata has sparked much discussion in the cataloguing world.
Note that despite its name a folksonomy is not a taxonomy. A taxonomy is the process, within subject-based classification, of arranging the terms given in a controlled vocabulary into a hierarchy. Folksonomies move away from the hierarchical approach to an approach more akin to that taken by faceted classification or other flat systems.
With the rise of the Internet and increased use of digital networks it has become easier to both work in an informal and adhoc manner, and as part of a community. In the late 1990s Weblogs (or blogs), a Web application similar to an online diary, became popular and user centred metadata was first created. In late 2003 delicious, an online bookmark manager, went live. The ability to add tags using a non-hierarchical keyword categorisation system was appended in early 2004.Tagging was quickly replicated by other social software and in late 2004 the Folksonomy name, a portmanteau of folk and taxonomy, was coined by Thomas Vander Wal.
Robin Good is quoted as saying that "a folksonomy represents simultaneously some of the best and worst in the organization of information." There is clearly a lot to be learnt from this new method of classification as long as you remain aware of the strengths and weaknesses.
Over time users of the Internet have come to realise that old methods of categorisation do not sit comfortably in a digital space, where physical constraints no longer apply and there is a huge amount to be organised. Search services like Yahoo's directory, where items are divided into a hierarchy, often seem unwieldy and users appear happier with the Google search box approach. With the rise of communities on the Web there has also come about a feeling that meaning comes best from our common view of the world, rather than a professional's view.
While there is no doubt that the professional cataloguing will continues to have a place, both off the Internet and on, there has been recent acceptance that new ways of adding metadata, such as folksonomies, need more exploration, alongside other areas like the semantic Web. The two models of categorisation (formal and informal) are not mutually exclusive and further investigation could only help us improve the way we organise and search for information. If nothing else folksonomies have achieved the once believed unachievable task of getting people to talk about metadata!
Podcasting has been described as "a method of publishing files to the internet, often allowing users to subscribe to a feed and receive new files automatically by subscription, usually at no cost." [10].
Podcasting is a relatively new phenomena becoming popular in late 2004. Some of the early adopters regard Podcasting as a democratising technology, allowing users to easily create and publish their own radio shows which can be easily accessed within the need for a broadcasting infrastructure. From a technical perspective, Podcasting is an application of the RSS 2.0 format [11]. RSS can be used to syndicate Web content, allowing Web resources to be automatically embedded in third party Web sites or processed by dedicated RSS viewers. The same approach is used by Podcasting, allowing audio files (typically in MP3 format) to be automatically processed by third party applications - however rather than embedding the content in Web pages, the audio files are transferred to a computer hard disk or to an MP3 player - such as an iPod.
The strength of Podcasting is the ease of use it provides rather than any radical new functionality. If, for example, you subscribe to a Podcast provided by the BBC, new episodes will appear automatically on your chosen device - you will not have to go to the BBC Web site to see if new files are available and then download them.
Note that providing MP3 files to be downloaded from Web sites is sometimes described as Podcasting, but the term strictly refers to automated distribution using RSS.
There are several potential applications for Podcasting in an educational context:
Although there is much interest in the potential for Podcasting, there are potential problem areas which will need to be considered:
It would be advisable to seek permission before making recordings or making recordings available as Podcasts.
It is advisable to gain experiences of Podcasting initially as a recipient, before seeking to create Podcasts. Details of Podcasting software is given at [12] and [13]. Note that support for Podcasts in iTunes v. 5 [14] has helped enhance the popularity of Podcasts. You should note that you do not need a portable MP3 player to listen to Podcasts - however the ability to listen to Podcasts while on the move is one of its strengths.
When creating a Podcast you first need to create your MP3 (or similar) audio file. Many recording tools are available, such as the open source Audacity software [15]. You may also wish to make use of audio editing software to edit files, include sound effects, etc.
You will then need to create the RSS file which accompanies your audio file, enabling users to subscribe to your recording and automate the download. An increasing number of Podcasting authoring tools and Web services are being developed [16] .
Instant messaging (IM) is growing in popularity as the Internet becomes more widely used in a social context. The popularity of IM in a social context is leading to consideration of its potential for work purposes in providing real time communications with colleagues and co-workers.
Popular IM applications include MSN Messenger, Yahoo Messenger and AOL Messenger [17]. In addition to these dedicated applications a number of Web-based services also provide instant messaging facilities within the Web site, such as YahooGroups [18]. The JISCMail list management service also provides a Web-based instant messaging facility.
Instant Messaging software can provide several benefits:
Instant messaging fans appreciate the immediacy of communications it provides, which can be particularly valuable when working on small-scale concrete tasks.
There is a need to be aware of potential problems which can be encountered when using instant messaging software:
Critics of instant messaging argue that, although IM may have a role to play for social purposes, for professional use email should be preferred.
Instant messaging may prove particularly useful when working with remote workers or if you are involved in project work with remote partners. However in order to make effective use of instant messaging tools there is a need to implement a policy governing its usage which addresses the problem areas described above.
The following additional resources may be useful: