Did someone say unique values? It't time for `Set`! This is an exercise where ES6 can really shine, `Set` is made to store unique values, and that's exactly what we're asked to do here. Let's take it step-by-step.

There are many ways to solve this challenge. Obvious helpers are JavaScript's built-in methods to convert between strings and Unicode values, String.fromCharCode() and charCodeAt().

Not sure what they were going for there, because this exercise is literally just checking `typeof` the input value to see if it's a `boolean`.

Regex Time! Let's brush up on our Regex skills to solve this challenge. There's an excellent guide by MDN that explains everything you need to know to solve this exercise simply and elegantly.

This one is actually fairly easy, so this will be a short post. We'll do some basic array manipulation and make a `Map` for the DNA base pairs. This creates a mapping of each of the 4 letters to it's partner.

This one looked too easy at first. Replace a substring? This is what String.prototype.replace is for ... but freeCodeCamp added an additional constraint - preserve case

For this challenge we are passed an array of objects, and a source object. We should check if all the key-value pairs of the source are found in an object of the array, and if so return it.

This could be messy. freeCodeCamp asks us to write a converter for roman numerals. Let's use modern JavaScript to solve the problem elegantly.

For this freeCodeCamp challenge we'll write a function to compute the symmetric difference between two arrays.

The first intermediate challenge is a bit of a warmup question - we'll write a function that take an array of exactly 2 numbers, and returns the sum of those 2 numbers and all numbers in between.