diff --git a/BasicCalculator.java b/BasicCalculator.java
new file mode 100644
index 0000000..f4200eb
--- /dev/null
+++ b/BasicCalculator.java
@@ -0,0 +1,88 @@
+import java.util.Scanner;
+
+public class BasicCalculator {
+    
+    // Method for addition
+    public static double add(double num1, double num2) {
+        return num1 + num2;
+    }
+
+    // Method for subtraction
+    public static double subtract(double num1, double num2) {
+        return num1 - num2;
+    }
+
+    // Method for multiplication
+    public static double multiply(double num1, double num2) {
+        return num1 * num2;
+    }
+
+    // Method for division
+    public static double divide(double num1, double num2) {
+        if (num2 == 0) {
+            throw new ArithmeticException("Cannot divide by zero");
+        }
+        return num1 / num2;
+    }
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        boolean continueCalculation = true;
+
+        System.out.println("Basic Calculator");
+
+        while (continueCalculation) {
+            // Input for first number
+            System.out.print("Enter first number: ");
+            double num1 = scanner.nextDouble();
+
+            // Input for second number
+            System.out.print("Enter second number: ");
+            double num2 = scanner.nextDouble();
+
+            // Input for operation
+            System.out.print("Enter operation (+, -, *, /): ");
+            char operation = scanner.next().charAt(0);
+
+            double result;
+
+            // Switch case to handle different operations
+            switch (operation) {
+                case '+':
+                    result = add(num1, num2);
+                    break;
+                case '-':
+                    result = subtract(num1, num2);
+                    break;
+                case '*':
+                    result = multiply(num1, num2);
+                    break;
+                case '/':
+                    try {
+                        result = divide(num1, num2);
+                    } catch (ArithmeticException e) {
+                        System.out.println(e.getMessage());
+                        continue;
+                    }
+                    break;
+                default:
+                    System.out.println("Invalid operation");
+                    continue;
+            }
+
+            // Output the result
+            System.out.println("The result is: " + result);
+
+            // Ask if the user wants to perform another calculation
+            System.out.print("Do you want to perform another calculation? (yes/no): ");
+            String continueInput = scanner.next();
+            if (!continueInput.equalsIgnoreCase("yes")) {
+                continueCalculation = false;
+            }
+        }
+
+        // Close the scanner
+        scanner.close();
+        System.out.println("Calculator closed.");
+    }
+}
diff --git a/NumberGuessingGame.java b/NumberGuessingGame.java
new file mode 100644
index 0000000..f9b6082
--- /dev/null
+++ b/NumberGuessingGame.java
@@ -0,0 +1,60 @@
+import java.util.Random;
+import java.util.Scanner;
+
+public class NumberGuessingGame {
+
+    public static void main(String[] args) {
+        // Create a Scanner object for reading input from the console
+        Scanner scanner = new Scanner(System.in);
+        
+        // Create a Random object for generating random numbers
+        Random random = new Random();
+        
+        // Generate a random number between 1 and 100
+        int numberToGuess = random.nextInt(100) + 1;
+        
+        // Set the maximum number of attempts
+        int maxAttempts = 10;
+        
+        // Initialize the number of attempts used
+        int attempts = 0;
+        
+        // Variable to track if the user has guessed the number
+        boolean hasGuessedCorrectly = false;
+        
+        // Game introduction
+        System.out.println("Welcome to the Number Guessing Game!");
+        System.out.println("I have selected a number between 1 and 100.");
+        System.out.println("You have " + maxAttempts + " attempts to guess it.");
+        
+        // Game loop
+        while (attempts < maxAttempts) {
+            // Increment the number of attempts
+            attempts++;
+            
+            // Prompt the user for a guess
+            System.out.print("Attempt " + attempts + ": Enter your guess: ");
+            int userGuess = scanner.nextInt();
+            
+            // Check if the user's guess is correct
+            if (userGuess == numberToGuess) {
+                hasGuessedCorrectly = true;
+                break;
+            } else if (userGuess < numberToGuess) {
+                System.out.println("Your guess is too low.");
+            } else {
+                System.out.println("Your guess is too high.");
+            }
+        }
+        
+        // Check if the user guessed the number correctly
+        if (hasGuessedCorrectly) {
+            System.out.println("Congratulations! You've guessed the number correctly in " + attempts + " attempts.");
+        } else {
+            System.out.println("Sorry, you've used all " + maxAttempts + " attempts. The number was " + numberToGuess + ".");
+        }
+        
+        // Close the scanner
+        scanner.close();
+    }
+}
diff --git a/TemperatureConverter.java b/TemperatureConverter.java
new file mode 100644
index 0000000..bc063d2
--- /dev/null
+++ b/TemperatureConverter.java
@@ -0,0 +1,41 @@
+import java.util.Scanner;
+
+public class TemperatureConverter {
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+
+        System.out.println("Enter the temperature to convert: ");
+        double temperature = scanner.nextDouble();
+
+        System.out.println("Enter the scale to convert from (C, F, or K): ");
+        String scaleFrom = scanner.next();
+
+        System.out.println("Enter the scale to convert to (C, F, or K): ");
+        String scaleTo = scanner.next();
+
+        double convertedTemperature = convertTemperature(temperature, scaleFrom, scaleTo);
+
+        System.out.println("The converted temperature is: " + convertedTemperature);
+    }
+
+    public static double convertTemperature(double temperature, String scaleFrom, String scaleTo) {
+        double convertedTemperature = 0;
+
+        if (scaleFrom.equals("C") && scaleTo.equals("F")) {
+            convertedTemperature = (temperature * 9/5) + 32;
+        } else if (scaleFrom.equals("C") && scaleTo.equals("K")) {
+            convertedTemperature = temperature + 273.15;
+        } else if (scaleFrom.equals("F") && scaleTo.equals("C")) {
+            convertedTemperature = (temperature - 32) * 5/9;
+        } else if (scaleFrom.equals("F") && scaleTo.equals("K")) {
+            convertedTemperature = (temperature - 32) * 5/9 + 273.15;
+        } else if (scaleFrom.equals("K") && scaleTo.equals("C")) {
+            convertedTemperature = temperature - 273.15;
+        } else if (scaleFrom.equals("K") && scaleTo.equals("F")) {
+            convertedTemperature = (temperature - 273.15) * 9/5 + 32;
+        }
+
+        return convertedTemperature;
+    }
+}
\ No newline at end of file
diff --git a/ToDoList.java b/ToDoList.java
new file mode 100644
index 0000000..f56fa8a
--- /dev/null
+++ b/ToDoList.java
@@ -0,0 +1,113 @@
+import java.util.ArrayList;
+import java.util.Scanner;
+
+class Task {
+    private String description;
+    private boolean isCompleted;
+
+    public Task(String description) {
+        this.description = description;
+        this.isCompleted = false;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public boolean isCompleted() {
+        return isCompleted;
+    }
+
+    public void markAsCompleted() {
+        this.isCompleted = true;
+    }
+
+    @Override
+    public String toString() {
+        return (isCompleted ? "[X] " : "[ ] ") + description;
+    }
+}
+
+public class ToDoList {
+    private ArrayList<Task> tasks;
+
+    public ToDoList() {
+        tasks = new ArrayList<>();
+    }
+
+    public void addTask(String description) {
+        tasks.add(new Task(description));
+    }
+
+    public void deleteTask(int index) {
+        if (index >= 0 && index < tasks.size()) {
+            tasks.remove(index);
+        } else {
+            System.out.println("Invalid task number");
+        }
+    }
+
+    public void markTaskAsCompleted(int index) {
+        if (index >= 0 && index < tasks.size()) {
+            tasks.get(index).markAsCompleted();
+        } else {
+            System.out.println("Invalid task number");
+        }
+    }
+
+    public void displayTasks() {
+        if (tasks.isEmpty()) {
+            System.out.println("No tasks in the list.");
+        } else {
+            for (int i = 0; i < tasks.size(); i++) {
+                System.out.println((i + 1) + ". " + tasks.get(i));
+            }
+        }
+    }
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        ToDoList toDoList = new ToDoList();
+        boolean exit = false;
+
+        while (!exit) {
+            System.out.println("\nTo-Do List:");
+            toDoList.displayTasks();
+            System.out.println("\nOptions:");
+            System.out.println("1. Add Task");
+            System.out.println("2. Delete Task");
+            System.out.println("3. Mark Task as Completed");
+            System.out.println("4. Exit");
+            System.out.print("Choose an option: ");
+
+            int choice = scanner.nextInt();
+            scanner.nextLine();  // Consume the newline
+
+            switch (choice) {
+                case 1:
+                    System.out.print("Enter task description: ");
+                    String description = scanner.nextLine();
+                    toDoList.addTask(description);
+                    break;
+                case 2:
+                    System.out.print("Enter task number to delete: ");
+                    int deleteIndex = scanner.nextInt() - 1;
+                    toDoList.deleteTask(deleteIndex);
+                    break;
+                case 3:
+                    System.out.print("Enter task number to mark as completed: ");
+                    int completeIndex = scanner.nextInt() - 1;
+                    toDoList.markTaskAsCompleted(completeIndex);
+                    break;
+                case 4:
+                    exit = true;
+                    break;
+                default:
+                    System.out.println("Invalid choice. Please try again.");
+            }
+        }
+
+        scanner.close();
+        System.out.println("To-Do List application closed.");
+    }
+}