Can I update my unlocked iPhone 4?

I have an iPhone 4.It's 5.1.1… I'm completely illiterate when it comes to my phone. It's unlocked to any gevey sim thingy or whatever it's called (all I know is that it can take any kind of sim card). I was just wondering if I can update it without my phone being relocked? Has anyone tried it before?

It sounds to me that when you say unlocked you mean unlocked for any network. So you can use any mobile carrier. If that is true updating to the latest ios will have no effect on your unlocked status. And it will still work with whichever carrier you choose.