If you are receiving an over-the-air (OTA) digital TV signal, you will need a set-top box if your TV does not have a built-in digital tuner. A set-top box converts the digital TV signal into an analog signal that your TV can understand.
If you are receiving a cable or satellite TV signal, you may or may not need a set-top box. Most cable and satellite TV providers provide their customers with a set-top box that includes a digital tuner. However, some providers offer a "cable card" option that allows you to use your own set-top box.
If you are streaming digital TV content over the internet, you will not need a set-top box if your TV has built-in internet connectivity. You can simply connect your TV to the internet and start streaming content using a streaming app like Netflix or Hulu.
Here is a table summarizing the different scenarios and whether or not you need a set-top box:
| TV Type | Signal Type | Set-Top Box Needed? |
|---|---|---|
| Traditional analog TV | Any | Yes |
| Digital TV with built-in digital tuner | OTA, cable, satellite | No |
| Digital TV without built-in digital tuner | OTA | Yes |
| Streaming TV with built-in internet connectivity | Internet | No |
| Streaming TV without built-in internet connectivity | Internet | Yes |