Thank you for your interest in the Genome Browser.
That file corresponds to our RepeatMasker track (http://genome.ucsc.edu/cgi-bin/hgTrackUi?db=hg38&c=chr1&g=rmsk
). On the description page there is additional information on how the data were generated, and the different classes (including DNA/RNA classes).
Let us know if you have any further questions on this data on anything else we can help with.
I hope this is helpful. Please include gen...@soe.ucsc.edu
in any replies to ensure visibility by the team. All messages sent to that address are archived on our public forum. If your question includes sensitive information, you may send it instead to genom...@soe.ucsc.edu
UCSC Genomics Institute