You're given the choice to perform a quick or more secure format (in case the computer is not being kept) just like when you install from DVD.
The reset option is a complete reinstall (
link).
No! Bleepingcomputer got it wrong.
It amazed me so many people are retards think reset mean a complete reinstall Windows but will not format hard drive, when they want clean install Windows then they inserted DVD or USB to booted into Windows setup to do quick format hard drive to have full clean installation of Windows. Reset actually did same procedures, it will be very helpful to people who had no experience with manually format hard drive and clean install Windows.
What people should had done simply clone OS partition from HDD to SSD then boot SSD into recovery to do Reset and put DVD or USB in and Windows RE will do all works automatically remove files (quick format) or full clean drive (full format) hard drive and clean install Windows.
Refresh = complete reinstall Windows
Reset = format hard drive and clean install Windows
Microsoft explained what refresh and reset actually did to Windows 8, same procedures with 8.1 and 10.
http://blogs.msdn.com/b/b8/archive/2012/01/04/refresh-and-reset-your-pc.aspx
Refresh Windows 8, 8.1, 10
1.The PC boots into Windows RE.
2.Windows RE scans the hard drive for your data, settings, and apps, and puts them aside (on the same drive).
3.Windows RE installs a fresh copy of Windows.
4.Windows RE restores the data, settings, and apps it has set aside into the newly installed copy of Windows.
5.The PC restarts into the newly installed copy of Windows.
Reset Windows 8, 8.1, 10
1.The PC boots into the Windows Recovery Environment (Windows RE).
2.Windows RE erases and formats the hard drive partitions on which Windows and personal data reside.
3.Windows RE installs a fresh copy of Windows.
4.The PC restarts into the newly installed copy of Windows.