Glossary

read (end, cb)

A function that retrives the next chunk. All readable streams (sources, and throughs) must return a read function.

reader (read,...)

A function to create a reader. It takes a read function as the first argument, and any other options after that.

When passed to pipeable or pipeableSource, a new function is created that adds .pipe(dest)

Lazy vs Eager

Lazy means to avoid doing something until you know you have to do it.

Eager means to do something early, so you have it ready immediately when you need it.

Source

The first stream in the pipeline. The Source is not a reader (not writable).

Sink

The last stream in the pipeline. The Sink is not readable.

Through

The stream (or streams) in the middle of the pipeline, between your source and sink. A through is a reader and readable.

Push vs Pull

A pull-stream is a stream where the movement of data is initiated by the sink, and a push-stream is a stream where the movement of data is initiated by the source.

Reader vs Writable

In push streams, destination streams (Through and Sink), are writable. They are written to by the source streams.

In pull streams, destination streams read from the source streams. They are the active participant, so they are called readers rather than writables.