Many common practices and accepted programming models do not address important challenges inherent in designing systems for modern computer architectures. To be successful, distributed systems must cope in an environment where components crash without responding, messages get lost without a trace on the wire, and network latency fluctuates. These problems occur regularly in carefully managed intra-datacenter environments - even more so in virtualized architectures.
To help you deal with these realities, Akka provides:
Multi-threaded behavior without the use of low-level concurrency constructs like atomics or locks — relieving you from even thinking about memory visibility issues.
Transparent remote communication between systems and their components — relieving you from writing and maintaining difficult networking code.
A clustered, high-availability architecture that is elastic, scales in or out, on demand — enabling you to deliver a truly reactive system.
Akka’s use of the actor model provides a level of abstraction that makes it easier to write correct concurrent, parallel and distributed systems. The actor model spans the full set of Akka libraries, providing you with a consistent way of understanding and using them. Thus, Akka offers a depth of integration that you cannot achieve by picking libraries to solve individual problems and trying to piece them together.
By learning Akka and how to use the actor model, you will gain access to a vast and deep set of tools that solve difficult distributed/parallel systems problems in a uniform programming model where everything fits together tightly and efficiently.