# 1. Introduction

Subtraction is one of the four elementary arithmetic operations. While the act of subtracting two numbers is straightforward, implementing it in a new programming language is a fundamental step for many beginners. This guide focuses on creating a Swift program that subtracts two numbers, giving insights into variable usage, arithmetic operations, and output in Swift.

# 2. Program Overview

This Swift program aims to subtract one number from another and then display the result to the console. Using Swift's variable declaration, arithmetic operations, and the built-in print function, we will achieve our goal.

# 3. Code Program

``````// Declare two numbers for the subtraction operation
let num1 = 8.0
let num2 = 3.0

// Perform the subtraction
let difference = num1 - num2

// Print the result to the console
print("The difference between \(num1) and \(num2) is \(difference)")
``````

### Output:

```The difference between 8.0 and 3.0 is 5.0
```

# 4. Step By Step Explanation

1. let num1 = 8.0: We begin by declaring a constant named num1 and assigning it a value of 8.0. The let keyword in Swift is used for declaring constants, which means once a value is assigned, it cannot be modified.

2. let num2 = 3.0: Another constant named num2 is declared, assigned a value of 3.0.

3. let difference = num1 - num2: This line carries out the subtraction operation. The values of num1 and num2 are subtracted, and the result is assigned to a new constant named difference.

4. print("The difference between \(num1) and \(num2) is \(difference)"): The result is then displayed using Swift's print function. We utilize string interpolation, represented by the \(variableName) syntax, to embed the values of the constants directly within the output string.