Hidden partitions after cloning

This is a computer I built several years ago (E6300).
I have upgraded from Windows 8.1 to Windows 10 Pro.
I have cloned the HDD to an SSD. (I eventually figured out how using Macrium Reflect. There was another D: partition for which I used Aomei Partition Assistant to combine it with C:.)
This is what Disk Management shows now:



Notice that the recovery partition is empty, although there is something in the other hidden partition.
1. What is typically in a recovery partition? Anything related to using Create a Restore Point?
2. What might be in the other (350MB) hidden partition?
3. Can either of these be safely deleted? Not that the space is needed but I'd just like to know.

I understand that a partition ahead of C: cannot be combined with C:, but the unused 450MB recovery partition could be.

Suggestions/discussion appreciated.

P.S. I cloned another computer and the recovery partition ended up being called D:. ???

The recovery partition is probably not empty despite what Disk Management shows. You won't have the necessary permission to see what's in a Recovery partition hence the apparent '100% free'. If all is well, the WinRE recovery environment should be there. Open a Command Prompt (Admin) and type reagentc /info to find out if the Recovery partition is in use. If it is in use, it should say:

Windows RE location: \\?\GLOBALROOT\device\harddisk0\partition3\Recovery\WindowsRE

Restore points are kept in the hidden folder 'System Volume Information' on the root of the drive to which they refer.

I just had to reinstall Win10 on a client's computer and the 'hidden' partition on it contains the Win8 Factory Restore files, more than 17GB and labeled as OEM Recovery, used to put the computer back to its as-shipped condition.

Berton said:

I just had to reinstall Win10 on a client's computer and the 'hidden' partition on it contains the Win8 Factory Restore files, more than 17GB and labeled as OEM Recovery, used to put the computer back to its as-shipped condition.

At 450MB it's a bit small for that. It's the typical size for a Windows 10 recovery environment.

You can see what's in a Recovery Partition by using MiniTool Partition Wizard. Right-click on the partition and select 'Explore'.

Bree said:

At 450MB it's a bit small for that. It's the typical size for a Windows 10 recovery environment.

You can see what's in a Recovery Partition by using MiniTool Partition Wizard. Right-click on the partition and select 'Explore'.

At over 17GB it obviously includes all the bloatware that came installed on the computer.

I was referring to Jambe's recovery partition, which is shown as 450MB in the screenshot.