Java 5, also known as Java 1.5, was released in September 2004 and introduced several significant features that enhanced the Java programming language. Key additions included generics, which allow for stronger type checks at compile time, and enhanced for loops, simplifying iteration over collections. Another important feature was the introduction of annotations, which provide metadata about the program elements. Java 5 also included the Java Virtual Machine (JVM) improvements and the Java Development Kit (JDK) enhancements, making it easier for developers to create robust applications. Overall, Java 5 marked a major evolution in the Java platform.