Originally Posted by Kneez

Short answer: no.

For many years I used maps to figure out my distance and I used a watch to figure out my time. You don't really NEED a computer for anything. I bought my first one last fall. I really do like to know my mileage without having to use a map and knowing my speed is kinda fun. But you know, people rode, raced, toured, etc for decades without them. They are fun to have and pretty convenient but they are not a necessity.