Luckily, inserting PNG files into your PowerPoint presentation requires no special procedure or attention. To begin, click on the INSERT PowerPoint Ribbon and then click on the PICTURE icon (see Figure 1). When the INSERT PICTURE window opens (see Figure 2), locate the PNG file you want to insert into PowerPoint and click the INSERT button.

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You have now inserted your PNG file into PowerPoint. From here you can manipulate, move, or resize the image just as you can with other image formats such as JPG, GIF, and BMP. For advanced users, PNG files support transparency like GIF files. Transparent areas in a PNG file may be specified by pixel or by the use of alpha channels.
Using transparency, you can create some interesting effects in PowerPoint. For example, by using transparent images, you can create a layering effect that visually describes some business process, organizational chart, or any other information where development of images in front of an audience in real time helps convey your message.

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PNG files also create far fewer artifacts than the more popular JPG image format. Artifacts are a byproduct of the compression process. Since JPG uses a lossy data compressions algorithm, artifacting is one of its byproducts.
PNG files are, therefore, well suited to images that contain text, line art, and other high-contrast imagery. The JPG format was largely created for photographic images and is actually a better choice when you need to display high-quality photographs in your PowerPoint presentations. PNG files do tend to be quite a bit larger than JPG files so if space is a major consideration, stick with JPG.