I'm not sure what category wiki I should choose!

All PBwiki wikis provide the same basic functionality, including PBwiki's ease-of-use and speed.

The three different packages differ in terms of specific features that appeal to each group.

Individuals, for example, get a basic wiki with straightforward access controls and a limited amount of storage. On the other hand, the product is free of charge, and free of ads.

Educators get a slightly different plan with features that individuals don't need, but are essential for teachers and schools, like an Acceptable Use Policy.

Businesses get the most functionality, including increased storage, advanced access controls, and the ability to integrate with corporate single sign-on solutions like Active Directory, but are required to pay for their service once they have finished trying out the product and are using it on a regular basis for their business.

No one plan is better than the other; rather, the plans are designed to meet the different needs of the different target audiences.