The Build command performs an incremental build that compiles all resources modified since the last build. To trigger an incremental build, either:
The Rebuild All command rebuilds all workbench resources that have an associated builder. You can select to rebuild all workbench resources by selecting from the workbench menu bar Project > Rebuild All.
The Build Project command executes an incremental build limited to one project. This option is available from the context menu of any project resource in the Packages view.
The Rebuild Project command rebuilds all resources contained in a project. This option is available from the context menu of any project resource in the Packages view.