# is-stream [](https://travis-ci.org/sindresorhus/is-stream) > Check if something is a [Node.js stream](https://nodejs.org/api/stream.html) ## Install ``` $ npm install --save is-stream ``` ## Usage ```js const fs = require('fs'); const isStream = require('is-stream'); isStream(fs.createReadStream('unicorn.png')); //=> true isStream({}); //=> false ``` ## API ### isStream(stream) #### isStream.writable(stream) #### isStream.readable(stream) #### isStream.duplex(stream) #### isStream.transform(stream) ## License MIT © [Sindre Sorhus](https://sindresorhus.com)