There are many applications available for editing your photos. Programs range from the free and simplistic e.g. Windows Paint to the complex and expensive e.g. Adobe Photoshop (although the new cloud based version of PS is easier to work into your budget). Which application you should choose depends on your goals. You probably don’t want to buy Photoshop if all you are going to do is make some minor sharpening, exposure, saturation, or other simple corrections to the .jpg files you shoot with your phone or point and shoot camera. Likewise, you don’t want to use Paint if you are shooting raw images with your high end DSLR or other similar type of camera.
Select from the Editing Software menu items for more on this subject and leave comments if you have a favorite software program that you would like to tell us about.