in-memory-data-grid

I am novice in hazelcast and I have a few questions. As I understand hazelcast comes with two entities HazelcastInstance (as I understand it is server) and HazelcastClient . These entities even packed into different jars. I have noticed that in our project we use only HazelcastInstance . I have asked collegues why don't we use HazelcastClient . As I understand their explanation HazelcastInstance has more possibilities than HazelcastClient . Thus HazelcastInstance = HazelcastClient + AnotherFeatures But for me it strange that these entities packed to different packages if it is truth. Please