Widget is a fancy word for tools or content that you can add, arrange, and remove from the sidebar(s) of your blog. Widgets make it easy to customize the content of your sidebar(s).
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You can benefit greatly by using widgets in your WordPress blog. To define them further, they are small boxes that contain a specific type of information or application for your users. You can install widgets into any area of your WordPress blog that has widget areas available. Some themes have more widget areas than others. You can add widgets to sidebars, footers, posts, and more. You can also make customized extra widget areas in your blog.
To learn how to install widgets into your WordPress sidebar, start with this video tutorial…