Introduction and get started with Swift

Swift and its Introduction

Swift is a programming language that is used to create apps for Apple devices, such as the iPhone and iPad. It is a powerful and versatile language that can be used to create a wide variety of apps, from simple games to complex business applications.

Swift is a relatively new language, but it has quickly become one of the most popular languages for developing iOS apps. This is because Swift is easy to learn and use, and it produces code that is both fast and efficient.

In this article, we will introduce you to the basics of the Swift programming language. We will discuss what Swift is and what it is used for. We will also go into detail about some of the fundamental concepts of Swift, such as variables, constants, and integers.

Constants and Variables: Constants are values that cannot be changed once they are declared. This is useful for things like mathematical constants, such as pi, or the number of days in a week.
Variables are values that can be changed once they are declared. This is useful for things like the score in a game, or the user's input.

Example:
// Constant
let pi = 3.14159


// Variable
var score = 0

In the above example, the constant pi cannot be changed, but the variable score can be changed. This means that we can write code to increment the score each time the player scores a point.

Declaring Constants and Variables: 

To declare a constant, use the let keyword.
To declare a variable, use the var keyword.

Example:
// Constant
let name = "Alice"


// Variable
var age = 25

Type Annotations: Type annotations are used to specify the type of a constant or variable. This is not required, but it can help to prevent errors.

Example:
// Type annotation 

let numberOfPeople: Int = 10

The type annotation in the above example tells the compiler that the variable numberOfPeople is an integer. This means that the compiler will check to make sure that we are only assigning integer values to numberOfPeople.

Naming Constants and Variables: Constants and variables should be named in a way that is descriptive and easy to understand.
Avoid using abbreviations or acronyms.

Example:
// Good variable name 

var totalCost: Double



// Bad variable name 

var tc: Double

The good variable name in the above example is descriptive and easy to understand. The bad variable name is not descriptive, and it could be easily confused with other variables in the code.

Printing Constants and Variables: To print a constant or variable, use the print() function.

Example:
print(name) // Prints "Alice" 

print(age) // Prints 25

The print() function is a useful way to debug your code and to see the values of your constants and variables.

Next: Swift: Comments, Integers, Floating Point Numbers