There are a million ways of creating prototypes or wireframes for a website. How complex a prototype needs to be depends. Sometimes a quick sketch on a piece of paper is enough material to start building the idea “for real”. But sometimes we need something a lot more substantial to visualize a product. I often use Axure in those cases. I find that it’s a fast and easy tool to create interactive prototypes.*
* Well, at least semi easy. It’s not entirely pain-free. For example, you need to remember to avoid å, ä, ö in your file names or you can’t always open the prototype on a mac.