JavaScript executes code line by line from top to bottom. This process is called execution flow.
Understanding how JavaScript reads and runs your code is very important because it helps you predict what will happen when a program runs and avoid logical mistakes.
When you know the execution flow, you can write programs that behave correctly and are easier to debug.
How JavaScript Executes Code
- JavaScript reads the code from the first line
- Each statement is executed in order
- Variables are created before they are used
- Functions are executed when they are called
- Errors stop the execution if not handled
Knowing this flow helps developers control program behavior.
This example shows that JavaScript runs code one line at a time. The messages appear in the same order as they are written in the program.
Here, JavaScript first prints the message before the function call, then executes the function, and finally continues with the remaining code.
This shows how execution flow moves into a function and then comes back to the main program.
This example shows that when JavaScript finds an error, it stops executing the remaining code.
Understanding execution flow helps developers prevent such issues and write safer, more reliable programs.