A guestbook is one of the oldest forms of Web interaction. It allows visitors to post commentary and compliments on the contents of the board. Although a guestbook has little implementation cost in terms of time and energy, it also inspires the least community spirit. Therefore, a guestbook is a better addition to a traditional Web site than it is a feature used with most community sites.

The two most popular guestbook extensions for Joomla are Easybook and Jambook. Since a guestbook is fairly simple in both conception and implementation, these extensions provide very similar features. Your choice will likely be dependent on which extension most appropriately compliments the visual aspect of your site.

Easybook
Easybook is an excellent simple guestbook component. One of the best features of the component is the extensive anti-spam protection such as CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart) image generation, live email address confirmation checking, and automated word filter. The word filter list can be defined through the Administrator interface of the component and configured to automatically send an email to the administrator if someone attempts to post an item on the prohibited word list. Easybook can also be set to ping the supplied email server of the poster and ignore the post if the server isn’t valid.

With all of the difficulties in running a virtual community (mostly in added workload and time), it might seem to be a questionable undertaking. This is not the case. I am not trying to discourage the adoption of virtual community technologies but simply make you aware of some of the challenges in their deployment.

The greater your knowledge of the challenges before you attempt to create a virtual community, the greater the likelihood that you will be prepared for the difficulties and overcome them. A poorly implemented community is much more likely to be a failure than a poorly implemented Web site. The Web site will still garner visitors looking for the information it contains, while a failed online community will be like a ghost town with few tourists.

Despite any disadvantages to creating a community, the benefits are substantial:

Creating a virtual community is somewhat like making a movie. Before a single camera starts to roll, there is an entire process of preproduction ensuring that the actors are properly cast, the equipment is rented and functioning, the script is in place, and the department heads know what type of movie they are trying to make. If any of these areas are neglected, from the first day of shooting, the movie will stumble forward, and a vast amount of time and energy will likely be wasted.

Likewise, a virtual community is expensive in time to launch, difficult to attract visitors/contributors,  and poorly planned execution will make even a promising start fizzle into a disappointment. Although Joomla makes the deployment of the features simple, proper planning even for an incremental deployment is critical for site success. By being deliberate in your planning and construction of the new community site, you will minimize the chances of hard-won users becoming frustrated with a poorly working or confusing roll- out and leaving your site forever. The creation and deployment may be divided into roughly three stages.

Three Stages of a Virtual Community
Virtual communities are unlike most traditional Web deployments (such as a static site or online store) in that they derive their value from the intercommunication of a large user base. Under any circumstances, gathering this large number of users can take quite a bit of time. The creation of a virtual community is typically a gradual process, and a visitor surge does not provide the benefits it would on a traditional site. If your Web site was suddenly flooded with a million users overnight, it is unlikely that the site could retain those users for more than a short period of time. Furthermore, the first experience of these new visitors would be empty content and slow performance. Growth for virtual communities is organic because the community slowly discovers what the group has to offer.

Now that you possess the skills to program all three types of extensions (modules, components, and plug-ins), your development will probably require that you integrate any extension you create with the Joomla system. This means understanding how Joomla functions on an execution level, and likely being able to make calls to the Joomla framework.

 The complete Joomla framework is divided into a sizable number of packages, most of which are represented in an actual Joomla installation with a folder dedicated to the source files:

❑       Application Package — JApplication and related libraries are implemented as a factory class. The four classes extended from this package (JInstallation, JModel, JSite, and JAdministrator) make up the Joomla CMS application. Also included are the Data Access Object (DAO) libraries, including the abstract JModel class that is extended to create the classes JModelCategory, JModelComponent, JModelMenu, JModelModule, JModelPlugins, JModelSection, JModelSession, and JModelUser. It is located in the librariesjoomla directory.

Unlike modules that are all stored in the modules folder or components that all exist in the components folder, plug-ins are categorized and grouped within folders that define their categories. For example, plug-ins that provide search functionality are stored in the pluginssearch folder, while content plug-ins exist in the pluginscontent folder.

In the Plugin Manager, the category of plug-in is generally displayed in two places: as a prefix to the plug-in name and in the Type column. The name of each plug-in is preceded by the type. For example, the LDAP plug-in displays a name of “Authentication - LDAP.” The type of plug-in defines how the extension will be treated by the system.

The eight different types of plug-ins include the following: