Other taking up 2.2GB on Iphone 4?

I've restored my phone and deleted my apps and photos and there's still this huge block of yellow on my itunes screen that shows "Other" taking up that room on my phone. What is this other? Why is it taking up so much space? Can I find out what it is somehow?

This is memory that the iPhone needs in order to run. You can't recover it. All iPhones are like that.

Operating software

  • Why is the Other data taking up 5 GB in my iphone? I have 1 picture and 4 apps. I continuously have to delete everything because I have only less than 3 GB for everything. I did everything to deleting cookies to resetting my iPhone but it isn't working.
  • Why is other taking up so much space on my iPhone? - 1 And more importantly, what can I get rid of to get more space? I've deleted texts, calls, voicemails, emails, photos, songs, safari cookies & data, AND notes. What is going on? It's taking up around 3 GBs (or whatever) and it's killing me.
  • Why is other taking up 6.8 of my memory space on my iphone 5? On my iphone 5 "other" is taking up 6.8 of my data… What is this other and how do i reclaim my space? I've tried like resetting my phone and rebacking it up and stuff but nothing happened…
  • Why is other taking up 3.32 GB on my iphone? What is it? I got no calendar events. No reminders. Hardly any texts messages. No apps. No notes. No photos. No music. No "world clock". I have one alarm for when I get up in the morning. I literally have nothing on my phone, since I just updated it to iOS 7.0.4. Is there anything I can do to get rid of all this "other"?