The best analogy is to compare web hosting to commercial real estate. We provide the building space, the power, and the connectivity. You provide what goes inside of that space, whether it be your personal blog, e-commerce site, or company website.
In depth explanation: Web hosting is the mechanism by which a website becomes available to the world to see and access. To do so, your website (made up of html, css and php files) typically resides on a powerful specialized computer called a server in a building called a data center that houses thousands of servers in racks that host millions of websites. For example, You type in www.veerotech.net in your web browser and a service called DNS (Domain Naming System) asks an authoritative server “what is the IP address of www.veerotech.net?”. This IP address is like your physical home address and it is unique just like the IP address of the website you are wanting to visit. Once your computer knows the IP address, it routes the best path to get to the server in the data center where the website is hosted. All of this happens in milliseconds.