There are too many publishers publishing books about Ruby. The market is really very competitive. But, you hardly see many ObjC books in the market right now. T

There are too many publishers publishing books about Ruby. The market is really very competitive. But, you hardly see many ObjC books in the market right now. This may be the reason why ObjC book sale increases. If you are using Ruby, you don't have to worry about memory management at all. But, if you are using ObjC, you have to worry about memory management especially if you are developing iphone application.(only iPhone doesn't have GC.) Anyway, a GCC compiler can actually compile objC, so, it is not actually a Apple only language. Basically, any linux system with GCC compiler can compile objC too.