Since it's covered quite simply and very visibly in the article: yea, this is one ELI5 I'd prefer to not exist. At least skimming TFA is a reasonable pre-requisite IMO.

When the article assumes reader knowledge (especially very specific stuff) tho... there are quite a few very good responses here, it'd be a shame to reduce them. There are some extremely knowledgeable people lurking around here, and they're sometimes doing so for this kind of reason - to spread the knowledge. Plus context-specific Q&A can be far more effective than random googling / other articles / etc, as a learning tool.