In Swift, **optionals**, represented by the keyword **`Optional`**, handle the absence of a value. 

An optional has a default value of `nil`. It is used to set a variable or constant to contain no value in it. 

An optional is a value on its own and can be declared by appending the (`!`) or (`?`) character to the data type being declared. 

When an optional contains a value, it returns the keyword `Optional` and the value in parentheses.  

#    
## Example 1

#   
#  Output
```terminal
nil
```

The example above demonstrates how to declare an optional in `Swift`. A variable was declared and an optional type was initialized using the `?` character. 

Since no value was assigned to the variable, the print statement returned `nil`.

##   
## Example 2

var sample2: Int? = 3
print(sample2)
print(sample2!)

#    
#  Output
```terminal
Optional(3)
3
```
In the code above, an optional of type `Int` was declared and assigned a value of `3`. Since a value was assigned to the variable, it will have a return value of the form `Optional<value>`.

The second print statement unwrapped the optional and returned the value assigned to the variable.

> This type of unwrapping method should only be used if it is certain that the optional will have a value when accessed.  
 
##   
## Example 3

#    
## Output
```terminal
5
```
In the example above, an unwrapped optional was created with the `Int!` character. It automatically unwraps the value within the variable. 

> A fatal error will occur if no value was assigned to the variable.  

How to use Swift optionals

Swift optionals handle the absence of a value, using `nil`, `?`, and `!`. Examples show declaration, unwrapping, and handling in Swift.