The most important change in Java 8 is the introduction of lambda expressions. They enable faster, clearer coding and make it possible to use functional programming.
Java was created back in the '90s as an object-oriented programming language, with the idea that everything should be an object. At that time, object-oriented programming was the principal paradigm for software development. But, recently, functional programming has become increasingly popular because it is well-suited for concurrent and event-driven programming. This doesn't mean that we should stop writing code using object-oriented languages. Instead, the best strategy is to mix elements of object-oriented and functional programming. Adding lambdas to Java 8 ties in with this idea—Java is an object-oriented language, but now it has lambdas, we are able to code using the functional style too.
Let's look at this new feature in detail.