Saving your SHSH blobs is a good idea if you think there is ever the possibility that you may want to downgrade your iOS software. Apple only allows users to upgrade iOS, but if you save your SHSH blobs you will have the ability to downgrade to that version. This can be useful for anyone who wants to jailbreak their device using a former version of iOS software or if there was a feature that you preferred in your previous version.
How to Save your SHSH Blobs
1. You will need your 2nd or 3rd generation Apple TV, a micro USB cable and power cable.
2. Download TinyUmbrella on your computer for Mac or Windows.
3. Open TinyUmbrella.
4. Plug in the power cord to your Apple TV.
5. Wait about 10 seconds after plugging in the power and then plug in the USB cable.
6. TinyUmbrella should recognize your Apple TV after a few seconds.
7. Select Apple TV under Connected Devices.
8. Click Save SHSH. By default TinyUmbrella saves the SHSH blobs to an untitled folder on your desktop. If you want to change the location, go to Advanced and select where you would like them saved.
9. Your saved SHSH blobs will look something like the photo below. Keep them somewhere safe on your computer just in case you ever want to downgrade your Apple TV software.