The “let” keyword in swift

In swift, we use the let keyword to declare a constant variable, a constant is a variable that once declared, the value can not be changed.

Declaring constants

We can declare a variable in swift like below:

let myAge: Int = 27

Notice the let keyword above, we use it to denote that myAge is a constant and should hold the integer 27. Unlike variable declared using the var keyword, we cannot change the value of a constant once it has been assigned.

A constant is very similar to a variable except it value cannot be changed when declared.

Summary

It’s important that you keep the following in mind. You can declare a constant with the let keyword, constant have the same properties as a variable (var) which include type annotation, naming convention etc., except once a value has been assigned, the value cannot be changed