Streams sart using data, before it has finished loading. - ex) Before all the data could be stored >> we can pass it as a stream (Buffer) - ex) Send down it every time it fills. const readStream = fs.createReadStream('../docs/blog3.txt', {encoding: 'utf8'}); const writeStream = fs.createWriteStream('../docs/blog4.txt'); readStream.on('data', (chunk) =>{ //chunk: chunk of data. //on is event list..