Hi Lenita,
Dodging and burning is a method of creating or enhancing light and dark spots or areas in specific areas of a picture. You can make shadows and highlights as dark or as light as required. Imagine the waves at your local beach !! or a picture of a flag blowing in the wind.
Using Photoshop (all versions) or other similar programs (they all have more or less the same tools) you can create the light areas with the dodge tool and the dark areas with the burn tool. You can also set the strength of both tools plus one or two other settings.
Take a look in your tool bar for the tools and have a play. The more you dodge the lighter it gets and the more you burn the darker it gets. Always use these types of tools on it,s own layer as they are destructive tools.
Cheers

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