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Question 1

What is a computer program?

Answer 1

A set of instructions that tells a computer what to do.

Question 2

Why do computers need programs?

Answer 2

Without programs, computers are just empty machines.

Question 3

What is Java?

Answer 3

A popular programming language created in 1995 and owned by Oracle.

Question 4

Where is Java used?

Answer 4

Mobile apps, web apps, desktop apps, games, databases, and more.

Question 5

Why is Java popular?

Answer 5

it is platform-independent, secure, fast, and object-oriented.

Question 6

What does “Write Once, Run Anywhere” (WORA) mean?

Answer 6

Java code can run on any device with a Java Virtual Machine (JVM).

Question 7

What is source code?

Answer 7

The code written by a programmer before it is compiled or interpreted.

Question 8

What does an interpreter do?

Answer 8

Reads and executes code line by line.

Question 9

What does a compiler do?

Answer 9

Translates the entire source code into machine code before execution.

Question 10

Does Java use an interpreter or a compiler?

Answer 10

Java uses both: the compiler converts code into bytecode, and the JVM interprets it.

Question 11

Where can you download Java?

Answer 11

From oracle.com.

Question 12

What are two popular Java IDEs?

Answer 12

Eclipse and NetBeans.

Question 13

What must every Java program have?

Answer 13

At least one class.

Question 14

What is the name of the method where Java starts execution?

Answer 14

The main method.

Question 15

What is the correct syntax for the main method?

Answer 15

public static void main(String[] args) { }

Question 16

What does System.out.println(“Hello”); do?

Answer 16

Prints “Hello” to the console.

Question 17

How do you write a simple Java program?

Answer 17

public class Hello {
public static void main(String[] args) {
System.out.println(“Hello, Java!”);
}
}

Question 18

What is a statement in Java?

Answer 18

A command that performs an action, like printing text.

Question 19

Why is documentation important in Java?

Answer 19

t makes code easier to understand and maintain.

Question 20

What are good naming conventions for Java?

Answer 20

Classes: Start with uppercase (ComputeExpression).
Variables/methods: Start with lowercase (computeSum).

Question 21

How should Java code be formatted?

Answer 21

Use indentation and blank lines for readability.

Question 22

What are the three types of errors in Java?

Answer 22

Syntax errors – Found by the compiler.
Runtime errors – Cause the program to crash.
Logic errors – Produce incorrect output.

Question 23

What is a runtime error?

Answer 23

An error that happens while the program is running.

Question 24

What is an object-oriented language?

Answer 24

A language that organizes code using objects and classes.

Question 25

What makes Java secure?

Answer 25

Java runs inside the JVM, which protects the system from harmful code.

Question 26

What is the first step in writing a Java program?

Answer 26

Create a Java class with a main method and write code inside it.

Question 27

What do {} braces do?/What do () parentheses do?

Answer 27

Define a block of code./Enclose method parameters.

Question 28

What do [] brackets do?/ What do // double slashes do?

Answer 28

Define arrays./Create single-line comments.

Question 29

What is a logic error?

Answer 29

A mistake in the program’s logic that gives wrong results.

Question 30

What is a syntax error?

Answer 30

A mistake in code structure, like missing ;.

Question 31

Which of these is a reserved keyword in Java?

Answer 31

class

Question 32

What symbol is used for single-line comments in Java?

Answer 32

//

Question 33

What is the correct way to declare an integer variable in Java?

Answer 33

int number = 10;

Question 34

How do you start a multi-line comment in Java?

Answer 34

/*