Running scripts with node command in Node.js - Step-by-Step Execution

Concept Flow - Running scripts with node command

Write JavaScript file: script.js

↓

Open terminal/command prompt

↓

Type: node script.js

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Node reads script.js

↓

Node executes code line by line

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Output shown in terminal

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Script ends

This flow shows how you write a JavaScript file, run it with the node command, and see the output in the terminal.

Execution Sample

Node.js

console.log('Hello from Node!');

This code prints a message to the terminal when run with node.

Execution Table

Step	Action	Evaluation	Result
1	Node reads script.js file	Reads code: console.log('Hello from Node!');	Code loaded
2	Execute console.log statement	Prints 'Hello from Node!'	Message shown in terminal
3	End of script reached	No more code to run	Script stops

💡 Script ends after all lines are executed

Variable Tracker

Variable	Start	After 1	Final
No variables	N/A	N/A	N/A

Key Moments - 3 Insights

Why do I need to type 'node script.js' in the terminal?

Typing 'node script.js' tells the computer to use Node.js to run the JavaScript file named script.js, as shown in execution_table step 1.

What happens if I run 'node' without a file name?

Node will open an interactive prompt instead of running a file, so no script runs until you type code manually.

Why does the output appear in the terminal?

console.log sends output to the terminal where you ran the node command, as seen in execution_table step 2.

Visual Quiz - 3 Questions

Look at the execution table, what does Node do at step 2?

A Ends the script

B Reads the script file

C Prints the message to the terminal

D Waits for user input

💡 Hint

Check the 'Action' and 'Result' columns at step 2 in the execution_table

At which step does the script stop running according to the execution table?

A Step 3

B Step 1

C Step 2

D After step 3

💡 Hint

Look at the 'Step' and 'Result' columns to find when the script ends

If you change the file name to 'app.js', what command should you run to execute it?

A node script.js

B node app.js

C node run app.js

D run node app.js

💡 Hint

The command uses 'node' followed by the exact file name, as shown in concept_flow

Concept Snapshot

Run JavaScript files with Node.js using the command:
node filename.js
Node reads and executes the file line by line.
Output from console.log appears in the terminal.
Script ends when all code runs.
Use terminal or command prompt to run scripts.

Full Transcript

To run JavaScript code with Node.js, you first write your code in a file, for example script.js. Then, you open your terminal or command prompt and type 'node script.js'. Node reads your file and executes the code inside it line by line. If your code uses console.log, the messages will appear in the terminal. When Node finishes running all the lines, the script stops. This process lets you run JavaScript outside of a browser easily.