Why is the freezing point and the melting point of a liquid is the same?

Pure water's melting point and freezing point is both at 0 degree celcius. Freezing is heat loss while melting is heat gain. But why is this so? What is happening during this process? Molecules or what? Please answer my question instead of saying that the freezing point and the melting point doesn't need to be the same.

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…).