The PlayStation 4 will not support the use of external hard drives to store downloaded games or other data, Sony confirmed today in a post on the PlayStation Blog.
As part of the Ultimate FAQ on the PlayStation Blog, Sony revealed that the ability to hook up external drives to the PS4 is a feature not supported by the console.
The FAQ notes that users will be able to swap out and replace the console's stock 500GB hard drive, which is a a 5400 RPM SATA 2 model. Users can swap in new hard drives so long as they comply with those standards, are larger than 160GB and do not exceed a thickness of 9.5mm.
In August, Sony Worldwide Studios president Shuhei Yoshida confirmed in a tweet that content downloaded on the PS4 could not be saved to an external hard drive.