Baby carrier confusion!

Can someone please tell me the difference between the baby carriers? Ergo baby is priced at over 100$ and then you have the cheaper ones like infantino that's 30$ and baby Bjorn that's 85$. What's the difference with them all, especially with that big of a price gap? Help! First time mom here. Don't want to buy junk, but don't want to get ripped off if it isn't worth the $$