What's the difference between phonetic and Pronunciation

[WinterWolf90]

I am trying to get my iPad to pronounce my friends name who is Arabic. On my phone it does it correctly when I use Siri to call or text him, but my iPad it doesn't. I was wondering what the difference is between the phonetic and pronunciation options were? I'm using the phonetic options on both iPad and my iPhone because my contacts are synced, but I can't seem to make my iPad do it correctly when I use Siri.