Under Portal Manager > Tools & Administration > Categories you can create categories and subcategories and assign them to elements like users, helpdesk tickets and companies among many others. Using categories you can create a clear structure and categorisation of your elements - for example by assigning users (elements) to certain industries (categories).
You can create categories and subcategories as well as edit, move and delete existing ones in order to adjust the categories to your current needs.

Categories can be added by Portal Masters or members with the role "Contact Manager".
Categories for wikis get added in the area Tools & Administration > Categories > Wikis.

A Wiki article is a normal story (but written by your members), which gets stored in the menu which was defined to be the Wiki menu. With the function Stories (Website & CMS > Stories) the corresponding Wiki article respectively the desired story can be selected and deleted.

A tag cloud contains the most popular tags, independent of the element (e.g. blogs, wiki article, documents, etc.) they belong to. The single tags of the tag cloud can be clicked and the matching results get displayed.

A Wiki is a collection of terms in need of explanation. With Wikipedia the method established that authors write, edit and publish entries directly online, voluntarily and without a fee. A Wiki article is only one single article, the explanation of one term in the whole Wiki, in the collection of all terms.

There are several landing pages for the wiki available. Go to Network & Community > Wiki > General. In the area Menus & Articles you find the selection box Homepage which contains the options. Choose an option and save the settings.