Hosting is a service that gives your website a place to live on a special, always-on computer called a server, so that people can open your site at any time of the day or night.
An easy way to picture it: if your website were a shop, hosting would be the rented space in a building where the shop actually stands — with electricity and an address, open around the clock. Your site’s files (its text, pictures and design) are stored on that computer, and when someone types your address, the server sends them the page. You usually pay for hosting monthly or once a year, much like paying rent.
The quality of hosting directly affects how fast your site opens, how rarely it goes offline and how well it is protected — which is why choosing and tuning it well really matters. Hosting is not the same as the site’s name: the name people type is called a Domain, and it simply “points” to the hosting where the site lives.