Why would you ever use a constant when you could use a variable instead?

Hey Parker Rose,

Good question! You use a constant over a variable for values that you NEVER want to change in your code. This helps the compiler make better optimizations and naturally prevent a lot of bugs from occurring. There will be places in your code where if a specific value was able to be mutated, this could become problematic.

For example:

// Let's say we create a constant called daysInYear and assign it an Int value of 365
let daysInYear = 365
// Let's create a variable called daysInMonth
var daysInMonth = 31

By defining daysInYear as a constant, it is much SAFER to use this value in our code, as the number of days in the year should never change. (Yes, ignore the possibility of a leap year for this example). daysInMonth on the other hand, is best as a variable because the number of days in the month can change, depending on what month it is.

Good luck!