A thin client is a lightweight Ignite client that connects to the cluster via a standard socket connection. It does not start in JVM process (Java is not required at all), does not become a part of the cluster topology, never holds any data or used as a destination of compute grid calculations.
What it does is it simply establishes a socket connection to a standard Ignite node and performs all operations through that node.
The thin clients are based on binary client protocol making it possible to support Ignite connectivity from any programming languages. Presently the following thin clients are available for usage: