When you open PowerPoint 2013 for the first time, you’ll see that all slide examples in the Presentation Gallery are in widescreen aspect ratio with 16:9 proportions. This is in complete contrast to the typical standard slides with 4:3 aspect ratios that you saw in all older PowerPoint versions. For many of us who are living in a world with widescreen displays and projectors, this may be a blessing — but many others may not feel as blessed! Worse, there’s no obvious way for you to change these defaults so that you can always have 4:3 slides rather than 16:9. Microsoft probably made this change since widescreen is the common format for current displays nowadays — but to provide no option to choose an aspect ratio at the time of creating a slide is akin to providing zero control to the user.
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