application		Scientific and engineering applications
benchmark		Benchmarks and example programs
data-analysis-vis	Data analysis and visualization, 
			including computer vision
numerical		Numerical libraries and routines, including
			computational geometry
ppt			Parallel processing tools
  ppt-comm		Communication libraries
  ppt-exe		Execution and performance analyzers, including
			debuggers
  ppt-io		Parallel I/O systems
  ppt-env		Parallel programming environments
  ppt-pplang		Parallel programming languages and compilers
  ppt-pplib		Parallel programming libraries
  ppt-rts		Parallel runtime systems
  ppt-scr		Source code analyzers and restructurers
  ppt-misc		Miscellaneous parallel processing tools