const fs = require('fs');

const r = fs.createReadStream('file.txt');

const z = zlib.createGzip();

const w = fs.createWriteStream('file.txt.gz');

r.pipe(z).pipe(w);

streams is process(read and write) data piece(chunks) without completing the

whole read or write operation, and therefore without keeping all the data in 

memory.

There are four types of streams => readable streams, writable streams, duplex

and transform streams.

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