A web host is a service provider that places your web site on a computer which is connected to the internet. This then gives people who surf the internet a way to access your website. The computer that the web hosting company uses is typically just like the computer you have at home, the only difference being that it is set up to serve up web sites and is therefore called a “server”.
A web host will typically have a fast connection to the Internet and they may host thousands of web sites on many servers. The web host essentially rents out space to you so that you can get your website up on the world wide web.