Textual format Sequence annotation track format BED bed Browser Extensible Data (BED) format of sequence annotation track, typically to be displayed in a genome browser. bed.gz beta12orEarlier BED detail format includes 2 additional columns (http://genome.ucsc.edu/FAQ/FAQformat#format1.7) and BED 15 includes 3 additional columns for experiment scores (http://genomewiki.ucsc.edu/index.php/Microarray_track).