In PowerPoint, slides are sized for an onscreen slide show. They are displayed horizontally, with slide numbers starting from one, but there are features in PowerPoint that allow the user to change ...

Microsoft PowerPoint defaults to display slides in your business presentation in Landscape layout. This means that your slides resemble a landscape painting where the width is greater than the height.

You can change the PowerPoint text direction and make it go from right to left. You can change the orientation of the text to various positions such as Horizontal, Stacked, Rotate all text 90 degrees, ...