Introducing the Force.com IDE

The Force.com IDE is an extension to the standard Eclipse development tool for building,
managing, and deploying projects on the Force.com platform.

Installation

Force.com IDE is distributed in two forms: a standalone application, and a plugin to the
Eclipse IDE. If Force.com is your primary development language or you are not an existing
Eclipse IDE user, the standalone version is a good choice.The plugin version of the
Force.com IDE requires Eclipse, which you can find at www.eclipse.org. Only specific
versions of Eclipse are supported by the Force.com IDE. If you are already using Eclipse
but it’s an unsupported version, keep your existing Eclipse version and install the supported
version just for use with the Force.com IDE. Multiple versions of Eclipse can
coexist peacefully on a single computer.
Visit http://wiki.developerforce.com/index.php/Apex_Toolkit_for_Eclipse to learn
how to install the standalone and plugin versions of the Force.com IDE.