In JDK 11, you'll be able to use var with lambda parameters. However, this is just syntactic sugar. The reserved type name, var, was introduced in JDK 10, to enable developers to declare local variables without using an explicit data type (to let the compiler infer the data type during compilation). But implicitly-typed lambda expressions were already doing this by using only the variable name for their parameters, without their types (examples are included in the preceding section).