JavaScript Runtime Environment
What is a "runtime" environment?
the "runtime" environment is the code that runs your code
function isEven (num) {
if(num % 2 === 0) {
return `${num} is even!`;
}
}
console.log(isEven(10);
We have a program but...
How
do we
run it????
V8 Engine:
- Written in C++
- Compiles Code
- Runs Code (is the runtime)
Chrome Web Browser:
- Debugger
- Web and DOM API
- Uses the V8 Engine
JS File
- Needs a runtime to execute/run a program
V8 Engine:
- Written in C++
- Compiles Code
- Runs Code (is the runtime)
NodeJS
- File System API
- Server Side
- Runs on the V8 Engine
JS File
- Needs a runtime to execute/run a program
Why learn about the JS runtime?
- Makes debugging easier
- Understand Scope and Closure under the hood
- The ability to reason what the "this" keyword references
-
Read and reason through pre-written code
-
It is hard, most JS Developers don't have an understanding of this material