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

“Use let to make a constant and var to make a variable”

Excerpt From: Apple Inc. “The Swift Programming Language.” iBooks. https://itun.es/us/jEUH0.l