Eclipse - Workspace

Eclipse has this fundamental notion of 'workspace'.

A workspace is just a folder on your file system - something as simple as:
C:\users\joe\workspace

Eclipse uses this folder to keep all its projects. So for each Eclipse project, you will see a corresponding directory in the /workspace

In addition, you will see a directory called /.metadata - this is the place where Eclipse will keep all its workspace-wide settings.

For example, it will remember how you like your various editors configured, how you want to setup your run time configuration, how you want to connect to CVS or Subversion, which projects you have opened, etc

You can have multiple workspaces, for example:
C:\users\joe\workspace-my-projects
C:\users\joe\workspace-company-projects
C:\users\joe\workspace-experimental-projects

If you frequently switch between different versions of Eclipse, you might even have something like:
C:\users\joe\workspace\europa
C:\users\joe\workspace\helios
C:\users\joe\workspace\indigo

Everytime you open Eclipse, it will ask you which workspace you want to use, then load the settings and projects from that workspace.

Tip - Sometimes, due to strange reasons, your workspace can get corrupted and Eclipse will start throwing weird errors. Deleting the .metadata folder usually resolves these issues (but you have to redo all your workspace settings)