What is ExpressionEngine?

A content management system that empowers thousands of individuals, organizations, and companies around the world to easily manage their website.

Features Overview
Web Publishing

ExpressionEngine’s publishing features are broad, comprehensive, and highly flexible.

* Multiple Weblogs/Site Sections
ExpressionEngine supports an unlimited number of weblogs. You can separate your weblogs into independent pages, or you can put multiple weblogs on the same page.
* Custom Entry Fields
Each section can have its own unique set of entry fields. These can be input boxes, pull-down menus or textareas.
* Search Engine Friendly URLs
The URLs produced by ExpressionEngine do not contain query strings which are disliked by search engines. Rather, they mimic the directory structure of static sites.
* Custom Statuses
Create editorial work-flow by creating statuses that you can assign your entries to, like "first draft", "revision", "final edit", etc. You can color-code them too.
* Multiple Categories
Each entry can be assigned to multiple categories, and you can create as many unique category groups as you want.
* RSS and ATOM Syndication
With RSS, your content can be made available for syndication. ExpressionEngine supports all major syndication formats, including the new Atom format.
* Moblog Publishing
Email weblog entries and photos to ExpressionEngine using your mobile phone or email program.
* Relationships
You can create relationships between entries in different sections of your site, enabling information to be shared.
* Entry Versioning
The Entry Versioning feature lets you save previous revisions of your weblog entries, so you never lose any edits you make.
* Multi-Entry Editing
This feature permits multiple entries to be edited at one time, saving you time.
* Entry View Tracking
You can track up to four "zones" per entry so see where your entries are being viewed.
* Ping Servers
Each user can define their own servers to ping when new entries are added.
* HTML Formatting Buttons
Each user can store their own formatting elements that are available at the click of a button.
* URL Titles
Each weblog entry can be given a "human friendly" title for use with your comments or your permalink page.
* Sticky Topics
Weblog entries can be made "sticky", forcing them to always show up at the top of the page.
* Future Entries
You can post entries into the future and they won't appear on your site until that date.
* Expiring Entries
You can set an expiration date and your entries will be removed from your site automatically on that date.
* Pagination
This feature allows your users to view older entries by clicking "next" and "previous" page links.
* Article Pagination
You can split your articles into multiple pages.
* Image and File Uploading
Upload to multiple destinations, and limit uploads to specific user groups.
* Image Resizing and Thumbnailing
ExpressionEngine lets you resize images and create thumbnails, with support for the three major image manipulation protocols: GD, NetPBM, and ImageMagick.
* Image and File Browsing
View your uploaded images in the convenient File Browser
* Emoticons
Add "smileys" to your weblog entries and comments.
* Bookmarklet

Add-On Modules and Plugins

ExpressionEngine comes with 22 add-on modules and over 100 plugins.

* Discussion Forum
ExpressionEngine's Discussion Forum module is a complete community building solution that integrates seamlessly. Visit our community forums to see it in action. Note: The Discussion Forum is sold separately.
* Moblog
ExpressionEngine's Moblog Module enables you to send content to your website via email. Send photos to your image gallery, weblog entries to your blog, or data into your site sections simply by sending an email to your own account. You can have as many moblog accounts as you need, and each email you send can contain special tags which let you control how the content gets stored and displayed.
* Weblog
In ExpressionEngine, the term "weblog" refers to a section of your website, so even if you don't use EE to manage a blog you'll use the weblog module. The weblog module is the most flexible and powerful system we offer, enabling you to display your content in an almost infinite variety of ways. The Weblog Module supports advanced features, like custom data fields, multiple nested categories, sticky topics, workflow, publish and expiration dates, and other features found only in high-end content management solutions. You can even have multiple weblogs on the same page to create an ezine or complex brochure site.
* Wiki
The ExpressionEngine Wiki Module is a powerful, full-featured wiki that integrates with ExpressionEngine. Its a great way to host and manage community created content. Your site members can add and edit articles while your admins moderate the site as you see fit.
* Member Manager
ExpressionEngine supports an unlimited number of members and authors in a single installation, and comes with advanced member management tools so you can control exactly who can do what.

Powerful Member Groups allow you to restrict access and assign privileges to any area of your site, or within your administrative control panel. Create custom membership fields for required member information, enable editorial workflow if you have multiple authors contributing to your content, restrict pages to members of a certain level, and more.

Each member has their own profile management area where they can set their own preferences, manage their account, store notes, send email and private messages to other users, upload their photo, and more. Member management is integral to ExpressionEngine, so it provides the tools you need.
* Mailing List
Included with ExpressionEngine is a double-opt-in mailing list module that allows you to send mass email to subscribers of your site, or registered members. The Mailing List Module supports multiple sending protocols, HTML email, batch mode, and other advanced features, yet the user interface is a very simple to use.
* Simple Commerce
Introducing the ExpressionEngine Simple Commerce Module by pMachine. Fully integrate the purchasing power of PayPal into your existing ExpressionEngine site with this easy to use, flexible solution. Customizable email notifications for each product, member group assignment upon purchase, built in encryption, and automated purchase tracking through PayPal's Instant Payment Notification service give you the power you need to make your own store.
* Photo Gallery
Are you among the millions of people who take digital photos? Now you can organize and display them on the web with the ExpressionEngine Photo Gallery! And since it works seamlessly from within your ExpressionEngine installation, you no longer need to use separate programs to manage your photos and your web content.
* Blogger/MetaWeblog API
ExpressionEngine supports all three of the XML-RPC posting APIs (Blogger API, MetaWeblog API, and MT API), enabling you to use desktop software to send content to your site. Each author in your system can have their own API accounts, so different authors can post to different sections of your site.
* Commenting/Trackback
ExpressionEngine supports user commenting and trackbacks, both as separate features or combined together. Our comment module supports an array of display options, as well as the most comprehensive suite of security features of any system on the market.
* Recently Updated Sites
This module enables anyone using ExpressionEngine to run their own "recently updated sites" list. If you are familiar with sites, like weblogs.com, blogrolling.com, or blog.gs you'll know that these are sites that you can "ping" whenever you publish new content, adding your URL to the top of the list published at those sites. Well now you can run your own "recently updated sites" list at your website.
* RSS
RSS feeds are an important component of any professional website since they allow other sites to syndicate your content. ExpressionEngine supports all RSS protocols - .93, 1.0, 2.0, and Atom - and gives you the flexibility to cutomize your feeds as you desire.
* Email
The ExpressionEngine Email module lets you easily create feedback and tell-a-friend forms on your site. ExpressionEngine's flexible tag syntax makes the process of creating and managing these forms very simple, and since it supports all major Email protocols (SMTP, Sendmail, PHP Mail) it'll work in virtually any environment.
* Search
ExpressionEngine supports fast, flexible, and precise content searching, through simple and/or advanced search forms. As the site admin you can set search criteria, so that your users can search only the areas you specify, and you can have multiple search forms, each with different search criteria.
* Referrer
Anytime someone arrives at your website as a result of clicking a link at another site, ExpressionEngine will track it with its Referrer Module, and display that info in a list. This can be valuable information in determining how people are finding out about your site.
* Blacklist/Whitelist
The Blacklist and Whitelist Module is part of ExpressionEngine's extensive security features, designed to prevent spam in comments, trackbacks, referrers, etc. This module let you ban (blacklist) or allow (whitelist) URLs, IP addresses, and User Agents.
* Statistics
The ExpressionEngine stats module enables you to show a "who's online" list of users viewing your site at any given moment. You can also display various statistics, like the total number of entries, comments, trackbacks, members, page hits, etc.
* Query

More Product features and information here.