This package provides a high-level R interface to Unidata's netCDF data files, which are portable across platforms and include metadata information in addition to the data sets. Using this package netCDF files can be opened and data sets read in easily. It is also easy to create new netCDF dimensions, variables, and files, or manipulate existing netCDF files. This interface provides considerably more functionality than the old "netCDF" package for R, and is not compatible with the old "netCDF" package for R. Release 1.2 (2005-01-24) adds better support for character variables, and miscellaneous bug fixes. Release 1.3 (2005-03-27) is for miscellaneous bug fixes, and improves the documentation. Release 1.4 (2005-06-27) improves the efficiency, and adds small bug fixes. Release 1.5 (2006-02-27) adds support for byte variables, plus small bug fixes. Release 1.6 (2006-06-19) adds various bug fixes, plus support for making dimensions WITHOUT dimvars (coordinate variables), although I think this is a bad idea in general. ALSO, the default behavior for put.var.ncdf with unlimited variables and NO specified start and count parameters has changed! Before, the default was to append to the end of the existing variable. Now, the default is to assume a start of 1 along each dimension, and a count of the current length of each dimension. This really can be ambiguous when using an unlimited dimension. I always specify both start and count when writing to a variable with an unlimited dimension, and suggest you do as well. I may require this in a future release, as it seems to cause people problems.