Summary

The if expression can be used to only perform an effect if a condition is true

An else branch can be added to an if to do something if the condition is false

You can build up more complex series of conditions with if/else if/else

If you provide an else, and all branches evaluate to the same type, you can evaluate to a value from your if expression

Functions can call themselves using recursion, which combined with conditionals, can allow for more sophisticated programs

Block-like expressions that evaluate to unit do not need a semicolon to be turned into statements