Streaming devices provide an easy way for you to access your streaming services on your TV. They cost between $30-60 for a simple model or from $75 and up for a top of the line device. They usually plug into an HDMI port on your TV. Through them, you can download your streaming services’ apps and login to your account to watch your content on the big screen.
If you have a smart TV however, you often will not need a streaming device. This is because smart TVs often allow you to download the apps through which you can stream from Netflix et al. They may even come pre-installed on your smart TV. Check to see if your smart TV can run apps from your streaming services before purchasing your own device.