Declaring Constants and Variables
In Swift language to store temporary data we have to use variables and contants.Here we use var keyword to declare variables and let keyword to declare Constants.
var myvar=5
T declare a constant variable
let x=0
You can declare multiple constants or multiple variables on a single line var x=0,y=6
Type Annotations
                                        To define a data type we can use Type Annotations.
                                        var Message: String
                                        Here var Message has a type String 
                                    
We can change the value of a variable anytime but the value of constant can not be changes once it is set.
Printing Constants and Variables
                                        print method is used to print the value of varable or constants.String interpolation is used to  include placeholders 
                                        print(message) 
                                        print("Welcome Amit you got a \(message)")
                                    
Comments
                                        //This line is comment  
                                        Multiline comments start with a forward-slash followed by an asterisk (/*) and end with an asterisk followed by a forward-slash (*/): 
                                        
                                            /* here it is 
                                            Multiline comment */