Topic pages are used to organize communities and shared resources around specific topics, such as those listed on the Topics index, at https://publiclab.org/tags.
### Card text and image
On the top of topic pages, a card is shown with the topic name, and a short text (as in the above screenshot), and a background image may be shown. This is drawn from the very first paragraph of the wiki page bearing the same name; so for the topic `balloon-mapping`, the text is drawn from https://publiclab.org/wiki/balloon-mapping. The image is also taken from the lead image of the wiki page of that name.
If no matching wiki page exists, you'll see a prompt to create one.
### Engagement with Topics
Topic pages reveal how many people are engaging with a topic, and in what ways. The lower right hand corner of the lead image contains a number of "people discussing" -- this is the same as the number of "Followers"; followers are people who are subscribed to the topic.
Below the lead image at left, you can see some information about how many posts have been made in this topic, and by how many contributors. Below the lead image at right, you can see related tags, as well as options to sort the content by Type or by Likes, Views, or Last Updated:
### Aliases and redirects
If you want the lead text and image to be drawn from a **different** wiki page, you can make the matching wiki page a "redirect page" by adding the tag `redirect:______`, where `______` is replaced with the text from the URL of the page you really want.
For example, if you're on the topic page for `algal-blooms` but want the text and image to be drawn from `algae`, you can make a page at `https://publiclab.org/wiki/algal-blooms`, but then add the tag `redirect:algae` to that page. Then, anyone visiting `https://publiclab.org/wiki/algal-blooms` will be redirected to `https://publiclab.org/wiki/algae`, and the text and lead image of `/algae` will be used on the card for the topic `algal-blooms`. That is, the topic page can follow redirects to find the text and lead image to display.