I don’t know which icons you cannot understand the meaning. Basically, you use the Site Content and Structure page to manage both the content and structure of your SharePoint site collection. When you change the structure of the site, that change will be carried through to the site navigation. You can manage content by performing other actions on lists and list items. For example, check out or check in, publish, and copy items. Although I can’t find such list to explain the meaning of those icons, I think the document below can help you understand the function of “Site Content and Structure” better then you will know the meaning of each icon.
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