If I facetime over Wi-Fi on my iphone, will it show up on my bill?

Right now i just have my phone and then i have my ipod. I like to facetime my best friend which i use my ipod for and i don't have to worry about it showing up on a bill.well the phone i have right now is getting kinda old and i need to get a new one and thought about just getting an iphone. BUT if i get an iphone does that mean when i imessage or facetime people will it show up on my bill online? I think i heard someone say something out there being a setting on the iphone where you can turn the data something off (?) and it will only use the Wi-Fi? So it will work just like the ipod. I can facetime and imessage without it showing on the bill?

Nope it's on Wi-Fi but on 4G you'll get charged because your using data