Dalvik
Dalvik is a discontinued process virtual machine (VM) originally developed by Google for the Android operating system, designed to execute applications written in Java. It was optimized for mobile devices with limited memory and processing power, using a register-based architecture instead of the stack-based approach of the Java Virtual Machine (JVM). Dalvik was the primary runtime for Android apps from the platform's inception until it was replaced by Android Runtime (ART) starting with Android 5.0 Lollipop.
Developers should learn about Dalvik primarily for historical context and to understand the evolution of Android app development, as it was foundational to early Android versions (up to 4.4 KitKat). Knowledge of Dalvik is useful for maintaining or debugging legacy Android applications, analyzing older APK files, or studying mobile VM optimizations. It's also relevant for security researchers examining Android malware or vulnerabilities in older systems.