BLAST is a set of similarity search programs
designed to explore all of the available sequence
databases regardless of whether the query is
protein or DNA. It uses a heuristic algorithm
which seeks local as opposed to global alignments,
and is therefore able to detect relationships
among sequences which share only isolated regions
of similarity. It can be run locally as a full
executable, and can be used to run BLAST searches
against private, local databases, or downloaded
copies of the NCBI databases. It runs on Mac OS,
Win32, LINUX, Solaris, IBM AIX, SGI, Compaq OSF,
and HP- UX systems.