GSM Arena is incorrect, though. What UEFI Secure Boot does is disallow unsigned or unauthorised code to run at boot before the main OS. This is to prevent boot loader viruses from landing on your hard drive, and they are difficult to remove.
What this means for other OSes is that they need to support Secure Boot and have their OS signed with Microsoft's key to allow it to work. Quite a few Linux distros have already gone through with this and only a few that don't support Secure Boot, like some versions of Arch, CentOS or Gentoo, will need you to jump through a few hoops to get it working.
At the end of the day, it deals a blow only to Hackintosh builds and older software like XP or outdated Linux distros. What Microsoft and the rest of the software industry wants is for more people to virtualise these old OSes and embrace Secure Boot to improve overall system security.