Segment trees are really amazing when it comes to answering questions about ranges of numbers. They can make a big difference in many situations. Here are some reasons why they are so special:

1. Quick Query Responses: Using a segment tree, you can get answers to your questions in just $O(\log n)$ time. This is super helpful for both static data (data that doesn’t change) and dynamic data (data that does change). It’s much faster than the old way of doing it, which can take $O(n)$ time for each question.

2. Flexible Use: Segment trees can do many different kinds of tasks. They can help you find totals, smallest numbers, largest numbers, and even work with tricky things like finding the greatest common divisor (GCD) or making updates without having to redo everything. This means you can adapt segment trees for many different uses.

3. Space Saving: They do use some extra space—about $2n$—but this is a small price to pay for how fast they can find answers and handle updates.

4. Easy Updates: With segment trees, you can change values in just $O(\log n)$ time too. This is super useful if your data changes often.

In conclusion, segment trees are a great choice for quickly asking questions and making updates on ranges in an array. They are important tools in competitive programming and many areas of computer science.