Understanding Java: From JVM to Garbage Collection

Developed by James Gosling at Sun Microsystems in 1995, Java was initially designed for interactive television, but it was too advanced for the digital cable television industry at the time.

The Java Virtual Machine (JVM) enables Java's platform-independence. Code compiled to bytecode runs on any system with JVM, making Java incredibly versatile across different operating systems.

Java manages memory allocation and de-allocation automatically through Garbage Collection. This process identifies and discards objects that are no longer needed, preventing memory leaks.

Java provides a robust concurrency framework. With the java.util.concurrent package, developers can create multithreaded applications, managing threads efficiently with Executors and other concurrency utilities.

Classloaders are a unique feature of Java, enabling it to load classes at runtime. Java has a hierarchy of classloaders: bootstrap, extension, and system/application classloaders.

While Android uses the Java language, its runtime environment is not JVM but Dalvik (replaced by Android Runtime, ART). This difference means Java bytecode is converted to Dalvik bytecode.

Contrary to popular belief, Java can match and sometimes exceed C++ performance through Just-In-Time (JIT) compilation, which optimizes the bytecode into machine-level code during runtime.