Large data files can be difficult to work with in R,
where data generally resides in memory. This package encourages a
style of programming where data is 'streamed' from disk into R via
a `producer' and through a series of `consumers' that, typically
reduce the original data to a manageable size. The package
provides useful Producer and Consumer stream components for
operations such as data input, sampling, indexing, and
transformation; see package?Streamer for details.