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http://genome.ucsc.edu/FAQ/FAQformat.html#format1
BED format provides a flexible way to define the data lines that are displayed in an annotation track. BED lines have three required fields and nine additional optional fields.
track name=pairedReads description="Clone Paired Reads" useScore=1
chr22 1000 5000 cloneA 960 + 1000 5000 0 2 567,488, 0,3512
chr22 2000 6000 cloneB 900 - 2000 6000 0 2 433,399, 0,3601
If your data set is BED-like, but it is very large and you would like to keep it on your own server, you should use the bigBed data format. (binary)