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MyEclipse has two primary versions (apart from the "Blue Edition," referred to below): a professional and a standard edition. The standard edition adds database tools, a visual web designer, persistence tools, Spring tools, Struts and JSF tooling, and a number of other features to the basic Eclipse Java Developer profile. It competes with the Web Tools Project, which is a part of Eclipse itself, but MyEclipse is a separate project entirely and offers a different feature set.
Most recently, MyEclipse has been made available via Pulse, a provisioning tool that maintains Eclipse software profiles, including those that use MyEclipse. Additionally, MyEclipse is offering a customized version for IBM products, "MyEclipse Blue Edition," that adds specific support for Rational Software and WebSphere development. Currently, MyEclipse Blue Edition is only available for Windows, leaving Linux and Mac unsupported.