Summary
Highlights
A virtual machine is a program that replicates the functionality of a physical computer. Emulators are a prime example, tricking software into believing it's running on its native hardware when it's actually on a different machine. This allows older programs, like 1980s arcade games, to run on modern hardware without modification.
Game developers use emulators to test games on various platforms like consoles or smartphones from a PC before release. In server management, virtual machines allow a few physical servers to host numerous virtual servers, enhancing scalability and load balancing. If one physical server fails, others can seamlessly take over the load, making the failure transparent to users.
The Java programming language effectively uses virtual machines and intermediate code. Instead of needing specific compilers for each device, Java code is compiled into 'bytecode' (intermediate code). A Java Virtual Machine (JVM) on the target device then translates this bytecode into specific machine code, making Java highly portable across different platforms.