A Web page, the presentation of an Object in the Web, how it is seen in the browser and the Metadata of that is the representation. This means it is the HTML Web page that can be seen on the Web. A browser translates this HTML into a presentation format that can be read as humans.
The Representation defines the Presentation.
The differences between presentation and representation of a resource in the Web are:
The representation determines the presentation of a resource in the Web
The representation stands for a resource in the Web
The presentation of a resource in the Web is shown in a Web browser
