"I think this bit is slightly confusing. Is it a..."

Summaries \- Summaries appear in popovers and are widely seen by readers who want a brief introduction, so improving them or adding them to pages which lack an appropriate one is high\-value\. Definition pages \- Formal definitions of mathematical concepts\. These provide foundations for the rest of our content and allow people familiar with the topic to quickly pick up or refresh an idea\. Examples: Explanation pages \- Single page explanations of concepts, with different lenses for people with different backgrounds\. These are best suited to mid\-sized concepts, and should aim to teach them intuitively\. Full guides \- Multi\-page flexible guides to topics are Arbital's specialty\. If you're confident in your ability to explain a complex topic, considering helping to plan and create these \(talking to the community on Slack is usually a good idea, you'll get valuable feedback and assistance on your plans\)\. External resource lenses \- When there's an excellent explanation elsewhere on the web, we'd like people browsing Arbital to be able to find it\. We welcome new lenses, with links to and brief descriptions of high\-quality external resources, for existing Arbital pages \(but not standalone resources pages, we'd like at least a popover\-appropriate summary\)\.

I think this bit is slightly confusing. Is it a new lens per resource?

And what do you mean by standalone resource pages? Am I allowed to create a lens that's just resources, and does it require a summary?