Windows Backup

Despite its name and Microsoft's posturing, Windows Backup is not a comprehensive PC backup and restore solution. Instead, it is a collection of longtime Windows features with a newly centralized user interface that does very little and requires you to sign in with a Microsoft account (MSA).
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Microsoft claims that Windows Backup allows you to back up a wide range of items, including files, themes, settings, installed apps, and Wi-Fi information. But all of that is incorrect or exaggerated, and none of it is new to Windows Backup.

Here's what Windows Backup--or, really, Windows 11 when you sign-in with an MSA--does with that information.

Files. You can optionally sync--not back up--some of your important files with OneDrive, Microsoft's cloud storage service. To do so, you must enable OneDrive Folder backup and work within the confines of the small set of folders that feature uses. Or, you must work within the OneDrive file system structure and manually configure files to sync.
Themes. When you sign in to Windows 11 with an MSA, it saves details about the theme you've configured, including the background, the sound scheme, the color scheme, and the mouse cursor.
Settings. When you sign in to Windows 11 with an MSA, it saves some of the many Windows 11 settings you configured, but it's a tiny subset of the available settings.

Learn more: Microsoft documents the settings it backs up on the Microsoft Support website.

Installed apps. Windows 11 does not back up your apps. When you sign in to Windows 11 with an MSA, it saves a list of the names of the apps you installed and those apps you've pinned to Start or the Taskbar.
Wi-Fi information. When you sign in to Windows 11 with an MSA, it saves the credentials--the name (SSID) and associated password--for each secure Wi-Fi network you successfully connect to.

If you sign in to Windows 11 with an MSA, most of that will happen automatically. The one exception is files backup, which occurs via a OneDrive feature called Folder backup. In some cases, Windows 11 may try to enable this feature automatically, in which case your Desktop, Documents, and Pictures folders, and all their contents, sync between that PC and the OneDrive cloud storage service. If OneDrive Folder backup is enabled, then that sync also happens automatically.

Storage may be a concern. Microsoft provides just 5 GB of free cloud storage in OneDrive, and that may not be enough to store your backups. If you have a Microsoft 365 Personal, Family, or Premium subscription, you have 1 TB of OneDrive cloud storage available to you.

Of course, backing up the PC--or just some of the information on the PC, as is the case with Windows Backup--is only half the job. The other half is restoring that data. And here, Windows Backup also falls flat: There is no way to arbitrarily restore any of the files, themes, settings, installed apps, or Wi-Fi information that Windows Backup protects. Instead, you can...