Datasheet
WordPress also features pluggable functions. These functions enable you
to override specifi c core functions in a plugin. For example, the
wp_mail()
function is a pluggable function. You can easily defi ne this function in
your plugin and send email using SMTP rather than the default method.
All pluggable functions are defi ned in the
/wp - includes/pluggable.php
Core WordPress fi le.
You can use some predefi ned functions during specifi c plugin tasks,
such as when a plugin is activated or deactivated and even when a plugin
is uninstalled. Chapter 2, “ Plugin Foundation, ” covers these functions
in detail.
When Are Plugins Loaded?
Plugins are loaded early in the process when a WordPress powered web
page is called. Figure 1 - 1 shows a diagram of the standard loading process
when loading a page in WordPress:
Figure 1 - 1 illustrates the standard process when loading a page in
WordPress. The fl ow changes slightly when loading an admin page. The
differences are minor and primarily concern what theme is loaded: admin
theme versus your web site theme.
AVAILABLE PLUGINS
When researching available plugins you need to know where to fi nd WordPress plugins. You can
download plugins anywhere on the Internet, but this isn ’ t always a good idea.
FIGURE 1 - 1
As with any software, downloading plugins from an untrusted source could
lead to malware injected and compromised plugin fi les. It ’ s best to download
plugins only from trusted web sites and offi cial sources such as the offi cial
Plugin Directory.
O cial Plugin Directory
The fi rst place to start when researching available WordPress plugins is the offi cial Plugin Directory
at WordPress.org. The Plugin Directory is located at
http://wordpress.org/extend/plugins/ .
With more than 10,000 plugins available and well over 100 million plugin downloads, it ’ s easy
to see the vital role plugins play in every WordPress web site. All plugins available in the Plugin
Directory are 100% GPL and free to use for personal or commercial use.
Available Plugins
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