You are trying to install or open an app that didn't come from the Mac App Store but you got a message saying App can't be opened because it is from an unidentified developer. This is how you bypass it.
Photograph files taken with a digital camera also carry certain Exchangeable Image File Format (EXIF) data where you can see the camera settings that were set when the photo was taken.
Sometimes you don't want your Mac OS X Mountain Lion powered computer to go to sleep, here's a nice little trick how to temporary prevent a Mac from going into a sleep mode.
We have already learned how to create a bootable OS X Mavericks USB drive using a third party app, this time I will show you how to create one directly in Mac OS X.
If you are the kind of person you want to read what has been changed before updating an app you can disable the auto app update setting. Or enable if you want updates fully automated.