What is the difference between `let` and `var` in swift?

Question

What is the difference between let and var in Apple\'s Swift language?

In my understanding, it is a compiled language but it does not check

Answer 1

var is the only way to create a variables in swift. var doesn't mean dynamic variable as in the case of interpreted languages like javascript. For example,

var name = "Bob"

In this case, the type of variable name is inferred that name is of type String, we can also create variables by explicitly defining type, for example

var age:Int = 20

Now if you assign a string to age, then the compiler gives the error.

let is used to declare constants. For example

let city = "Kathmandu"

Or we can also do,

let city:String = "Kathmandu"

If you try to change the value of city, it gives error at compile time.