Output refers to information that a program produces. It can be
sent to the user via some output device.
User Interfaces: GUIs and TUIs
Graphical User Interface - Uses visual elements to let you
interact with a program.
User Interfaces: GUIs and TUIs
Terminal User Interface - A user interface that uses text and
symbols, rather than graphical elements.
Your First JavaScript Function
console.log()
console.log() is a function that displays a message in a terminal application.
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console.log("Hello world!");
Your First JavaScript Function
console.log()
console.log() is a function that displays a message in a terminal application.
1
console.log("Hello world!");
Sample
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Hello world!
Demo: Display a message of your choice using console.log().
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console.log("I love JavaScript!");
Demo
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I love JavaScript!
// Comments
Comments serve two key roles: documenting code and disabling it
temporarily for testing.
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// This line prints a friendly greeting to the console
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console.log("Hello, world!");
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4
// console.log("This line is disabled for testing purposes.");
// Comments
Comments are completely ignored when the program is executed.
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// This line prints a friendly greeting to the console
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console.log("Hello, world!");
3
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// console.log("This line is disabled for testing purposes.");
Sample
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Hello, world!
Key Terms
Function
Code that performs a specific action.
Output
Information that a program produces.
Console Output
Text displayed by a program in a command-line interface, like a
terminal.
Comments
Notes written within the code that are ignored by JavaScript,
used by to explain or clarify the code.
'F' → Fullscreen
Objectives
Writing and executing code
Displaying console output
Debugging potential syntax errors
Reading comments
Activity Tasks
Create a new JavaScript script named 1-1-output.js.
Complete each task individually.
Task 1: Write and Test
Write each line of code from the section making sure to stay
within the main method.
Run and test your project to ensure it executes as intended.
1-1-output.js
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console.log("Hello, world!");
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console.log("This class is taught by Mr. Mortimer.");
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console.log("You are currently visiting: https://skynest.nexus");
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console.log();// Display a blank line
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//
Task 2: Add More Code
Write the additional sections of output under your current code.
Run and test your project to ensure it executes as intended.
1-1-output.js
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console.log("Hello, world!");
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console.log("This class is taught by Mr. Mortimer.");
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console.log("You are currently visiting: https://sehs.io");
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console.log();// Display a blank line
5
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console.log("What is the answer to life, the universe, and everything?");
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console.log("The answer is 42.");
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console.log();
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console.log("Sally sells seashells by the seashore.");
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console.log("Sally wants to invite you to invest in a money making opportunity.");
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console.log();
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console.log("If you start to feel overwhelmed, just remember:");
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console.log("Mortimers don't quit, we get fired!");
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console.log();
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console.log();
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console.log("Sincerely,");
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console.log("Mr. Mortimer");
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// console.log();
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// console.log("Display this message for 1 extra credit point");
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//
Task 3: Write a Custom
Section
Output a three-line paragraph of your choice somewhere in the
program. Keep it school appropriate.
Run and test your project to ensure it executes as intended.
Task 4: Comments
There is a section of code that is 'commented out'. Uncomment the
code so that it executes when your program runs.
Run and test your project to ensure it executes as intended.
Sample Output
Your program output should something similar to the sample output
below.
Sample Output
Hello, world!
This class is taught by Mr. Mortimer.
You are currently visiting: https://skynest.nexus
What is the answer to life, the universe, and everything?
The answer is 42.
Sally sells seashells by the seashore.
Sally wants to invite you to invest in a money making opportunity.
If you start to feel overwhelmed, just remember:
Mortimers don't quit, we get fired!
Sincerely,
Mr. Mortimer
Display this message for 1 extra credit point
I also accept the following items for extra credit:
1. Expired mayonaise
2. A preserved eyeball
3. A VHS tape of a movie that nobody has heard of
Reflection Questions
You may write your reflection answers as comments at the bottom of
your code.
What is the primary function of console.log()? How does it relate to the idea of a program "speaking" to a
user?
Imagine you typed Cosnol.log() by mistake. What do you think would happen when you try to run your
program? Why is correct spelling so important in programming?
What was the most challenging part of writing your first line of
code?
Submission
Submit your activity and reflection answers to the appropriate
dropbox.
Writing and executing code 
Create a new JavaScript script named 1-1-output.js.