UCSC Roadmap Epigenomics Hub: "Summary" tracks

Question

[QVINTVS_FABIVS_MAXIMVS]

I'm using data from the Roadmap Epigenomics Data Complete Collection at Wash U VizHub Hub on UCSC.

Using the table browser, I noticed there are "Summary" tracks along with the "regular" tracks. I can't find the appropriate documentation. But what's the difference between the two?

[max]

The hub information contains an email address at Wash U where you can ask the original authors a question.