There are several ways to add a need, depending on the situation. All of these are available both from the Main Menu and from the Shopping List < page:
The Quick-Add a Need < page (the "Quick Need Adder") provides a way to rapidly enter several needs. However, it doesn't help you to find or enter standard needs. It also doesn't allow you to enter specific properties for the need(s). Instead, the need(s) simply inherit the properties of the folder they are created in. In some cases, this will work okay. In others, the need properties won't be specific enough to provide smart shopping lists. However, you can easily modify a need's properties at any time by opening the Need Properties page, accessible by clicking on a need name (hyperlink) and from the Need Actions Menu. It's more difficult to "standardize" your needs once they're created, though it can be done.
The Add a Need < page (the "Advanced Need Adder") requires a little more time and effort to enter a need, but it helps you to pick and use standard folders and needs, and you can specify the need's properties (e.g. description and inventory management data) in the same step in which you enter the need.
Here are a few general guidelines to decide which page to use:
Use the Quick Need Adder for:
Use the Advanced Need Adder for: