In order to have a successful website then it needs to be easy to navigate for the customer. It is essential that before the creation of the website you as the designer have an idea about layout, menus etc. so that it has a clear structure. The actual products may be brilliant but if the website is too difficult to navigate by the customer then you are going to lose sales.
This is a design tool used to organise navigation around a website. These set out the different menus that will be on the website. Often, if not always, not all the information will be able to fit under one menu so therefore it needs to be split up. The site map helps to do this, especially splitting up the primary and secondary information.
Here is the site map that I designed for my website using gliffy.com: