Why does my Voice Sound Different When It's Recorded?

Its so f"ckin worse when record via iphone or audacity.
But when i singing on Mic my sound is very good

Well when you speak normally, you hear the sounds from within your head i mean your sound reverberates inside your skull to give you the voice you are familiar with, but the recorded one has no such effect because it's simply recorded into the machine… And the recorded sound is what others hear, i mean that's how your voice sounds to others