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Go to a photo that you want to save. Open the image if necessary. Resize your browser window. Click and drag the photo onto your desktop. Release the click.
Open the message, document, or web page that contains the photo you'd like to save on your MacBook. Not all web pages permit images to be saved or downloaded. For example, you can't download pictures from the Instagram website. If the image is in a preview format (e.g., a result on Google), you'll first need to click the image to open it in full-size view. Some images, such as occasional images inserted into articles, serve as links to other pages. If clicking an image opens an unrelated page, click your browser's "Back" button to return to the original image. Click the yellow circle in the upper-left corner of the window that contains the image. This makes the window smaller so that your Mac's desktop is visible. Click and hold the image with your mouse pointer, then drag the image off of the edge of your browser window until it's suspended over the desktop. You should see a transparent version of the image appear when you drag it away. When you see a white + in a green circle appear over the thumbnail of the picture, release the click you were holding. This will place the image file on your desktop.