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Tag Introduction
ExpressionEngine Tags enable you to bring your templates to life, displaying dynamic information.
Tags let you integrate Modules and Plugins into your pages
ExpressionEngine comes with nearly 20 modules (weblog modules, commenting module, photo gallery module, etc.), as well as dozens of available plugins. Modules provide most of EE's core features, and plugins provide small enhancements.
Each module and plugin has its own tags that enable you use its features within your pages, so understanding Tags is a critical component of learning the system.
Important Concept: Every ExpressionEngine Tag has a corresponding Module or Plugin that it is designed to generate content from.
Note: The Modules and Tags section of the user guide has detailed information regarding every tag associated with each module. When you are ready to begin designing your own templates you will reference that section of the user guide the most.
Anatomy of a Tag
A typical ExpressionEngine tag is surrounded by "curly braces" and looks like this:
{exp:weblog:weblog_name}
Tag Segments
A tag typically has 3 segments. The segments in the above example are:
exp : weblog : weblog_name
The first segment, exp, tells ExpressionEngine that this is a tag. The second part, weblog, is the Module that the tag belongs to. The third part, weblog_name, is the specific function from within the module that you are using.
The above tag tells ExpressionEngine to invoke the Weblog Name function from the Weblog Module.
Most tags have three segments, although occasionally in the case of plugins, some will only have two.
Two Types of Tags
There are two kinds of tags: single tags and tag pairs.
Single Tags
Single tags are designed to return a single piece of information. A single tag does not have a closing tag.
This is a single tag:
{exp:weblog:weblog_name}
Tag Pairs
Tag pairs are designed to return a multiple piece of information. Tag pairs have both an opening and closing component. This is a tag pair:
{exp:weblog:entries}
Entry content
{/exp:weblog:entries}
The above tag tells ExpressionEngine to invoke the Entries function from the Weblog Module. You'll use this tag a lot in your templates.
Variables
Tag pairs usually contain variables between the tags. A variable look like this:
{title}
A variable represents a piece of information. This variable, for instance, might show the title of a weblog entry. Variables are used like this within tag pairs:
{exp:weblog:entries}
<h1>{title}</h1>
<p>{body}</p>
<div class="author">Posted by {author}</div>
{/exp:weblog:entries}
Parameters
Most tags can have parameters. Parameters modify the behavior of a tag, letting you control exactly what a tag displays.
Parameters are placed inside the opening tag, like this:
{exp:weblog:entries parameter="value"}
A typical tag with multiple parameters might look like this:
{exp:weblog:entries weblog="news"
orderby="date"
limit="10"}
The above tag will show 10 weblog entries written in the "news" weblog. They will be displayed in descending order.
Parameters give you the flexibility to tailor the output of each tag in a multitude of ways. Instead of choosing from several ready-made tags that do slight variations of a similar function, you can use the same tag in a variety of different ways by altering the parameters.
The Next Step
Guess what? You now know nearly everything there is to know about tags! Take a moment to browse your Control Panel Templates to see if you can identify tags and their components.
Then, in the Modules and Tags section of the user guide you'll find information on every tag available in ExpressionEngine. By adding these tags to your templates you bring your pages to life with dynamic information.