Difference Between Completion Handler and Blocks : [iOS]

Question

I am messed with both completion handler and blocks while I am using them in Swift and Objective-C. And when I am searching blocks in Swift

Answer 1

In short : Completion handlers are a way of implementing callback functionality using blocks or closures. Blocks and Closures are chunks of code that can be passed around to methods or functions as if they were values (in other words "anonymous functions" which we can give names to and pass around).