How can i stop my IP address being shown to whoever i send an email to?

Everytime i send someone an email from yahoo mail my IP address which is supposed to be personal shows up at the bottom saying 'this message comes from this IP address',and from this you can almost pin point someones house,yet when i receive an email i dont see their IP adress.Furthermore to contact yahoo and to get a reply is impossible.Thanks beforehand for your help.

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).