Does wifi affect data at all?

I would like to know, does wifi affect data at all, and if so, how?

No, it should not.
The only thing I know, is that if you have data turned on. And your WiFi stops working for some reason, it could automatically change to data, which can cost you lots of MB.

So, if your WiFi is good, it should not. And, your phone automatically prefers WiFi over data.

Posted via the Android Central App

You can set the phone to not automatically switch to mobile data, so if you lose wifi, you just lose wifi.

If you have them both enabled, some carriers have the phone set to prefer data, since that makes them money, so keep mobile data turned off when you're using wifi.