Eclipse is a platform or more simply an IDE. It is used mostly for Java development but can be used for other items as well.

Here are some links I have found useful:

• Eclipse download site is where you get the latest Eclipse IDE application
• Eclipse Tutorials--A nice collection of links. Where I found those below.
• Top-10-Tips-For-New-Eclipse-Users--I don't think many people who have been using Eclipse everyday know all these tips!
• Automation for the people: Improving code with Eclipse plugins--It shows how to add in useful plug-ins for those who want write better code.
• Eclipse and Tomcat from IBM.