Hosting a web site is the process of housing, serving, and maintaining files for a web site. These can either be done by one person or business or multiple entities.
In a sense when you house your web site, you rent space on someone else’s computer to hold your web site. The host then stores the files to your web site under your domain name so that anyone can access your site.
Maintaining files for a web site is the process of updating the content of a web site and reviewing the site for bugs or errors that may interfere in the experience that a visitor may have on a particular site.