Download pages for Updaters:

• Download Security Update 2016-005 for OS X 10.10.5 (468 MB)
  
  
• Download Security Update 2016-001 for OS X 10.11.6 (414.9 MB)

Per the about doc, these updates include the security content of Safari 9.1.3.
(If you're running any AntiVirus software in OS X, disable or remove it before updating, as it may interfere with applying updates like this.)

FYI on Nvidia Driver Updates: Users of Nvidia's web drivers should know that new OS X updates (versions or later build numbers after Security Updates) require updated Nvidia graphics drivers. (Some non-Mac EFI cards are not supported by default OS X drivers.) They usually appear first in Nvidia's driver prefs update check.
(Of course backup before any OS X update. As a test, you can disable the Nvidia web driver in its prefs (reverting to use of apple's installed driver on next reboot) before updating to see if your card is supported by Apple's driver before updating the OS. IIRC clearing NVRAM also resets the nvidia driver pref, but that also clears other settings like startup disk.)
(Update: Nvidia driver updates for above released Sept. 7th - added to Video topics page.)

About Safari 9.1.3 Update for OS X 10.9.5, 10.10.5, 10.11.6:
Available via software update (no download page) - here's the doc about the security fix in Safari 9.1.3 that lists another Webkit patch. (Per article on new Security Updates for OS X 10.11.6/10.10.5 above, they include fix in Safari 9.1.3.)

• About the security content of Security Update 2016-001 El Capitan and Security Update 2016-005 Yosemite
  
  
• About the security content of Safari 9.1.3

Page of How-To, Troubleshooting & Tips for Mac/OS X/iOS Users from Airplay to Thunderbolt.
  

August 30th-31st, 2016 News Archive
• Apple web page for Sept. 7th, 2016 Event Keynote
• Report: Apple Working on iPad Upgrades and Refreshed Mac Lineup
• Boot Camp Tip: Installing on High Capacity Disks
• D/L page for HP Printer Drivers v5.0 for OS X 10.9 and later
• D/L page for Xerox Printer Drivers v4.1 OS X 10.7 and later
• Apple sued over unresponsive iPhone 6 touchscreens
• Apple Developer News notes macOS Sierra Beta 8 available.
• Youtube iOS app v11.33 (iOS 8 and later)
• Apple Support Article Updates:
  - Printer and scanner software for El Capitan, Yosemite, and Mavericks
  - iCloud storage plans and pricing (added 2TB option)
  - iCloud storage upgrades and downgrades (ditto)

For links to older news pages, see the Archives.