When the official website to download kafka, see the following release:
So some students have to wonder, is it kafka version number is not 2.11, and 2.12 do? In actual fact, the previous version of the source code is compiled kafka Scala compiler version. kafka server-side code is completely written by Scala language, Scala also supports object-oriented programming and functional programming, the source compiled with Scala code written is the ordinary ".class" files, so criticize us say Scala is a language for the JVM Department, it's a lot of design ideas are praised.
Now you know the reason for the reference to kafka-2.11-2.1.1 version, the real number is actually version 2.1.1 kafka. So what is this 2.1.1 also said it? 2 shows the front of the large version, namely Major Version; 1 represents the middle of this small version number or version number, namely Minor Version; final 1 indicates good for the top version, which is Patch number.