Web Hosting is a type of service provided by companies that rent out server hardware (processors, RAM and hard disk drives) to clients along with a quota of Internet bandwidth depending on the type of contract.
The companies operate equipment and connectivity dedicated to the purpose of hosting websites to Internet users. There are a variety of different Internet packages available at different price points and at different locations around the world. Server equipment is usually housed in data centers that are designed to accomodate racks of equipment in a temperature controlled environment with security in a feasible way.
The contracts or web hosting packages are based on the offered amount of storage, whether the server machine is dedicated to a client or not and the connection speed and data quota. Due to the falling costs of hardware and Internet connections, users can find hosting packages at very low and sometimes no costs (supported by advertisements).