BAM (Binary Alignment Map)
BAM (Binary Alignment Map) is a data format used for mapping sequences of DNA. It is a compressed binary version of the data in the SAM format. It is classified as an alignment format, as is CRAM. This is as opposed to sequence-only, unaligned, formats such as FASTA and FASTQ.
An index of a BAM is stored in a format called BAI, also described in the spec.