A web hosting service is a type of Internet hosting service that hosts websites for clients, i.e. it offers the facilities required for them to create and maintain a site and makes it accessible on the World Wide Web. Companies providing web hosting services are sometimes called web hosts.
Typically, web hosting requires the following:
one or more servers to act as the host(s) for the sites; servers may be physical or virtual
colocation for the server(s), providing physical space, electricity, and Internet connectivity;
Domain Name System configuration to define name(s) for the sites and point them to the hosting server(s);
a web server running on the host;
for each site hosted on the server:
space on the server(s) to hold the files making up the site
site-specific configuration
often, a database;
software and credentials allowing the client to access these, enabling them to create, configure, and modify the site;
email connectivity allowing the host and site to send email to the client.
Until 1991, the Internet was restricted to use only "... for research and education in the sciences and engineering ..." and was used for email, telnet, FTP and USENET traffic—but only a tiny number of web pages. The World Wide Web protocols had only just been written and not until the end of 1993 would there be a graphical web browser for Mac or Windows computers. Even after there was some opening up of Internet access, the situation was confused until 1995.
To host a website on the internet, an individual or company would need their own computer or server. As not all companies had the budget or expertise to do this, web hosting services began to offer to host users' websites on their own servers, without the client needing to own the necessary infrastructure required to operate the website. The owners of the websites, also called webmasters, would be able to create a website that would be hosted on the web hosting service's server and published to the web by the web hosting service.