It is hoped that the site will be relatively intuitive for the majority of users, obviating the need for an entire manual. If something is very important to know then there will generally be some instructions or tips at the appropriate place in the user interface.
The site can certainly be useful to those who don't create an account, but without logging in one is limited to doing one-off searches and trying to build recipes that will disappear once you leave the site. Logging in allows you to save your receipes for future reference.
A recipe is just a collection of an arbitrary number of individual foods. Once a recipe has been created, you can view the entire nutritional profile for all of the ingredients together. Ingredients can be added to or taken away from an existing recipe at any time, and existing recipes can be used as templates for creating new, similar ones.
Foods and recipes that users find and save are searchable by everyone. What this means is that the more people use the site, the more foods and recipes will be searchable by everyone.
Current recipe:
No items in recipe.