The welcome page is the first page you see when you first launch eclipse. Its purpose is to introduce you to the product. Welcome content typically includes an overview the product and its features, tutorials to guide you through some basic tasks, samples to get you started, etc.
There are many possible forms of welcome, ranging from simple static text to elaborate extendable multi-page presentations.
One common form is known as the Universal Welcome, which defines a common page structure, allowing several products to share the welcome space. If your product is using the Universal Welcome, you can customize its appearance via preferences.