How a website appears in the browser
It’s important to understand, that a website is an application being ran on someones computer, know as a webserver, which is rarely restarted, always connected to internet and uses it’s CPU and memory only for running websites. Website appears on the network after it’s files are placed on the hard drive of one of those webservers, so webserver is actually hosting it. For the site to function properly, webserver should have a bunch of programms installed and some space on a hard drive as well.
Usually, hosting is a service provided by companies, that own data centers, those companies provide limited to a certain amount resources available per user, to be able to share one computer between few users at the same time and add extra costs for installing nesseccary programms and doing file and database backups, this is called virtual or shared hosting. There is still a possibility to rent an entire machine, usually called a dedicated server, for yourself only, however in that case you get it without programms and is forced to hire a system administrator or setup it yourself. Another popular option – is a cloud hosting, which is not a single physical computer, but instead some space and CPU power provided from a huge data center.
What software used to host this website
Basically, Google or Amazon and other huge IT companies offer hardware, then software companies rent it, install neccessary programs and manage them and offer hosting to end users, so as I do.
This particular website, and all my other websites are served from Google Compute Engine instance with PHP7.1, MariaDB, Nginx and Varnish installed on it, static content being delivered by Cloudflare CDN and emails processed by Mailjet. I manage all that myself.
Also i secure some of my websites with a free SSL provider SSLforfree.
Why would you need a hosting for website
The main purpose of making a website is to create a nice looking image of your business and implement advanced tools for sales. You can ofcourse use social networks to show your content, but a website is a lot more flexible.
This only applies successfully if the site is created on a professional level and is able to advance to the high positions of search engines and impress it’s visitors.