Backup and Restore (.cmp file): We use this feature when we want to make a backup copy of an entire site or subsite, or when we want to move an entire site or subsite to another server or location. Unlike Web packages, content migration packages include list data, and we cannot choose to include only specific site elements. some customizations or settings can be lost in the process. For example, the backup file does not include workflows, alerts, and properties stored at the site collection level. The backup file also does not include the Recycle Bin state or objects inside it. To use Backup and Restore, we must have administrator permissions to that site.
Site Template (.stp file): Use this feature when we want to create multiple Web sites that start with the same base content or site structure. For example, we may want all of the subsites created on a site to have a similar site structure, look and feel, and even content. We can do this by saving a site as a site template and adding it to the Site Template Gallery so that anyone can use the site as a template. Unlike Web packages, site templates can include list data if we want. We must have both administrator permissions to the Web site where we want to create the site template and write access to Site Template Gallery.
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