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Runtime system

Runtime system definition

A runtime system is an essential part of software that keeps computer programs running smoothly when you use them. It handles tasks like managing memory and dealing with any errors that may crop up. One example could be a programming language like Java. When you write a Java program and want to run it, the Java Virtual Machine (JVM) serves as the runtime system for that program.

See also: computer system

What does a runtime system do?

  • The runtime system ensures that programs use memory efficiently. It keeps track of where data and instructions are stored in memory — and cleans up unused memory to prevent slowdowns or crashes.
  • If a program runs into an error, the runtime system handles it gracefully. It might display an error message, allow you to save your work, and continue running the program without crashing.
  • When you use multiple programs simultaneously, the runtime system makes them share resources (e.g., CPU time and memory) fairly. Doing so prevents one program from slowing down others.
  • If a program needs additional components (e.g., a new feature or plugin), the runtime system can load them without needing you to restart the whole program.
  • It protects your computer and data by making sure programs don't access areas they shouldn't or perform malicious actions.
  • Some runtime systems use tricks to make programs run faster, like compiling code for improved speed.