JavaScript Basic Syntax Quiz for Grade 8

📚 Quick Study Guide: JavaScript Basic Syntax

• 💡 Variables: Use var, let, or const to store data. Example: let score = 100;
• ✍️ Statements: JavaScript instructions are called statements. Most end with a semicolon (;).
• 💬 Comments: Use // for single-line comments or /* ... */ for multi-line comments. Comments make your code easier to understand for humans and are ignored by the computer.
• 🔢 Data Types: Common types include Numbers (e.g., 10, 3.14), Strings (text like "Hello World"), and Booleans (true or false).
• ➕ Operators: Symbols that perform operations. For example, + (addition), - (subtraction), * (multiplication), / (division). The = sign is the assignment operator.
• 💻 Output: To show information in the browser's console (a special area for developers), use console.log("Your message here");
• ✅ Naming Rules: Variable names cannot start with a number and cannot contain spaces. They are case-sensitive (myVar is different from myvar).

📝 Practice Quiz

1. Which keyword is commonly used to declare a variable in JavaScript?

1. variable
2. var
3. string
4. declare

2. What is the main purpose of a semicolon (;) at the end of a statement in JavaScript?

1. To make the code bold
2. To separate statements and indicate the end of a line of code
3. To start a new paragraph
4. To create a comment

3. How do you write a single-line comment in JavaScript?

1. # This is a comment
2. <!-- This is a comment -->
3. // This is a comment
4. /* This is a comment */

4. Which command is used to display output or messages in the browser's console?

1. print("hello");
2. display("hello");
3. console.log("hello");
4. show("hello");

5. How do you correctly assign the text value "JavaScript" to a variable named language?

1. language = JavaScript;
2. language: "JavaScript";
3. language = "JavaScript";
4. "JavaScript" = language;

6. Which of the following is a valid variable name in JavaScript?

1. 1stNumber
2. my-variable
3. _userName
4. var

7. What does the + operator do when used with two numbers in JavaScript?

1. Subtracts them
2. Divides them
3. Adds them
4. Multiplies them