Confluence is an enterprise wiki that makes it easy for the team to collaborate and share knowledge.

Adding, sharing and finding content is very easy.

These benefits come with all the additional features needed to make it a part of the business:

Enterprise security
Simple installation and management
Attractive, user-friendly interface
Powerful tools for structuring and searching your wiki
Professional features such as PDF export and automated refactoring
An open API for extension and integration
Confluence's advantages:

Fine grained security with space and page level permissions.
Spaces allow to easily have multiple linked wikis.
Create a blog in every space with 'News'.
Pages, comments, blogs and attachments are all searchable.
Email integration, refactoring, PDF exporting, and more...
Collaborate with team members in geographically dislocated offices with Confidence.
Use Confluence as an intranet - it is easy to publish or find information with powerful and comprehensive indexing.
It offer possibility to replace the share drives - store and search documents centrally so that the team can always access the latest information.
Search everything - spaces, pages, blogs, attachments and even team email - to find the information the staffs need rapidly.
Monitor project or company developments with page and space watching.
Confluence is very extensible and interoperable. It is, quite simply, the most extensible wiki available.

In addition to the extension possibilities, which allow bidirectional information flow with your existing systems, Confluence also has other integration features:

Confluence is developed using HTML standards and is tested with all major browsers.
RSS and email allow to interact with Confluence from the staff daily work tools.
RPC plugins allow users to deploy SOAP or XML-RPC services within Confluence.
Themes allow users to skin Confluence to match their look and feel!
Java Servlets can be deployed directly onto the Confluence server, dynamically!
Hook into Confluence's event-driven architecture to drive other applications or systems from Confluence activity
Confluence will run on most of existing hardware and software platforms. It runs on all operating systems which have a JDK, with almost all JDBC compliant databases.