If we talk about www and development simultaneously then these things have their means the 'World Wide Web' is the network of computers from all over the world that communicate with each other using the HTTP protocol, a language that allows the transmission of web documents.
While on other hand if you talk about web hosting business then the information that you see from your web browser is contained in web pages. These web pages are kept on computers called web servers. Web hosting is about the storage of the web pages so that people can access them. It is possible to host your own websites yourself but the reasons stopping most people doing this is that there are issues to consider with having the right hardware and software to successfully host your web pages.
Using specialized companies that offer web hosting capabilities on their web servers will take most of these worries away from you but you will need to choose wisely and weigh up the costs and your needs. In addition to having access to a web server, you will also need to register a domain name that uniquely identifies your website. In this way you can understand the web hosting and development.