web hosting is renting space on a web server
In simple terms, web hosting is renting space on a web server. A website is not simply a domain name, it is a collection of files linked together by HTML code to display text and graphics on a computer. In order for anybody to see this collection of files you've created, it has to be housed on a computer somewhere that has access to the internet. Not just any computer will do, of course. A web server is a computer set up with special software that allows it to receive requests from the internet for the website files it has stored on it and to send those files out over the internet so that the requesting computer can display them. It is very much like a waiter in a restaurant taking your order and bringing the food that you ask for from the kitchen, hence the name "server."