Radix tree

A radix tree is like a special tree that helps us store and search for words or numbers really fast! Let's imagine that we have a book with a lot of words in alphabetical order. Now suppose we want to find a particular word, let's say "apple"! We can't just flip through every single page of the book until we find "apple", that would take forever! Instead, we can use a radix tree to make our search faster.

Imagine that we have a big empty tree. We will start by writing the first letter of each word at the top of the tree. So for example, we would write "a" at the very top of the tree if we are looking for words that start with the letter "a". Then, we look at each word in our book and see which words start with the letter "a". We write those words as branches that come out of the "a". So if our book has the words "apple", "ape", and "alligator", we would write those words as branches that come out of the "a" at the top of the tree.

Next, we look at the second letter of each word. We write the second letter on the next level of branches, but we make sure to connect them to the correct first letter. So we would write "p" as a branch that connects to "a", "e" as a branch that connects to "a", and "l" as a branch that connects to "a".

Now, we do the same thing for every subsequent letter in each word until we have written every word in the tree. So in the end, we would have a tree that looks something like this:

`a -> p -> p -> l -> e`

` -> e`

` -> l -> i -> g -> a -> t -> o -> r`

Now, if someone asks us if we have the word "apple", we can easily find it by starting at the top of the tree, and following the branches for each letter in "apple" until we reach the end of the word. This allows us to find words really fast without having to search through every single page of a book or list!