What is carbonation and how is it connected to the rock carboniferous limestone?

I want to basically if the formation of a limestone pavement is it through carbonation and does that pavement widen to make cavern then a gorge? don't go into to much dept because i'm a gcse student so i'm doing it at a very basic level.

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…).