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Paint is a feeble program in terms of photo editing and retouching, but it's not without its uses. Right-click and choose to open your photo in Paint, and you can easily rotate it, resize it, or crop parts of the image out. You can crop and zoom to “blow up” a specific part of the picture too, although image quality will suffer. Paint can save edited files in various popular formats, including PNG and JPEG.  Paint is also useful for adding text to an image. Be sure to select the transparent text box option so that the text box doesn't appear as an ugly white ribbon blocking out the image underneath. Most of Paint's other options are fine for doodling, but useless for photo editing. If you've lost your copy of Paint, download the superior Paint.NET program instead. It was started as a Microsoft project to replace Paint, and it has more features than the original. The link to download it is provided later in this article. The free version of Serif's elegant photo editing software may not have the features of a program like Photoshop, but it's a dream for gently editing photos. Red-eye reduction, color correction, and several basic filters and effects make this an ideal program for the person who wants to make a family reunion photo look a bit better. If your photos don't require extensive touch-ups, but you suspect they might look better with a bit of basic filter and layer manipulation, PhotoFiltre is the program for you. The program features a large number of professional, easy-to-use transparency and contour effects that can change the look and feel of nearly any photo. It's also very streamlined, and takes up hardly any space on your hard drive.  PhotoFiltre is free for private use, but if you plan to use it commercially (creating advertisements, for example), you'll need to pay for a license. The licensed version is somewhat more powerful than the free version. You can safely download PhotoFiltre 7 from the PhotoFiltre website.

Summary:
Use Microsoft Paint for basic adjustments. Grab Serif Photo Plus. Use PhotoFiltre to add filters and effects with ease.