Runtime definition

What is the runtime? And I don't mean "at run time" = as the program/script is running. I mean

The <your-inter开发者_StackOverflow社区preted-language-here> runtime

That's exactly what it means; it's the environment and data structures that keep track of everything that's going along as your program runs. It's not only interpreted languages that have a runtime environment, so does every compiled language. In C, the runtime is the environment variables and operating-system provided services that let the program interact with the rest of the system. In an object-oriented language, it's also all the tables of objects and classes and methods that get built to allow message passing to take place. In an interpreted language, it's the state of the interpreter, plus all of those other things. In general, I guess you could describe the runtime as "everything that happens that you didn't explicitly write yourself".

http://en.wikipedia.org/wiki/Run-time_system

a collection of software designed to support the execution of computer programs written in some computer language. The run-time system may provide software services such as subroutines and libraries for common operations, implementation of programming language commands, type checking, debugging, and even code generation and code optimization

In general, it usually refers to the support structure necessarily for running a program beyond what the programmer writes. For interpreted languages, this typically takes the form of an interpreter (usually coupled with common library of subroutines); for compiled languages that have runtimes, this typically is just a library of commonly-used shared subroutines.