A Web Host, or webhost, is a company that provides space on their computers for you to put your website files onto. If you're thinking hard right now, you might just be wondering well heck, why don't I just put my website files onto my own computer? Well you could, but it just wouldn't work...
Web Hosting Companies, Web Server Software and the DNS
Web Hosting companies install special Web Server Software onto their always-on computers which in connection with the Domain Name System (or DNS) allows anyone connected to the internet to view websites just by typing in a website address like www.youtube.com.
The 2 main types of Web Servers used by Web Hosting companies are:
- Linux (usually with Apache server for webpages) or
- Windows (usually with IIS server for webpages)
If you're buying webhosting it's good to know that these 2 options are mostly the same price nowadays, but you would normally only choose a Windows based server if you were going to develop your website with microsoft software eg Visual Basic, .NET or ASP.
The DNS or Domain Name System is like a telephone book for the internet. When you type in a website address like www.webmentor.ie your browser must perform a look-up to find the nameserver info (literally the name of the computer your website is on) so that it can route your request for that domain's webpage to the right webhost where those files can be found.
How does a Web Hosting Company store a Website?
When you get a website designed and developed, it ends up as a whole lot of separate files.
Your webhost allocates you a folder on one of their computers, along with a username and password to access it. You upload your files into that folder and you can create subfolders for organisational purposes - same as your own computer. To do the upload you'll normally use a FTP Client (a program that can transfer files from your computer to the web host's computer using a protocol called FTP - File Transfer Protocol).
A Webpage is different to Word
Unlike Word, where images and movies are embedded into the document, a webpage is always assembled at the last minute by the browser program (eg Microsoft Edge, Internet Explorer, Mozilla Firefox, Safari, Opera, etc).
The webpage that you see contains placeholders for images, sound, movies and so on.
When the webpage is requested, those files are also requested and put into place on the webpage (every noticed how images can be slow to load? That's because they're being called to come in and take their place on the webpage). That's why even a small website, say with only 5 webpages, might actually be made up as many as 100 separate files. Whereas a Word document, with 5 pages, is still only 1 file!
How do websites get "served up" by web hosts?
Let's say you type www.webmentor.ie into your browser. First thing that happens is a DNS look up. This works a bit like a telephone book service - your browser needs to know the name of the webhost computers that store the website files for this site. Once the browser has the nameserver info, it will route the request for the files it needs to display the webpage from the website address you requested.
When the webhosting company's computer receives the request from your browser, it sends ("serves up") a copy of all the files that make up the webpage back down to the browser program onto the computer that you requested them from in the first place. That's when you begin to see a webpage coming in. It's the browser's job to assemble these files onto one page - so if you have a slow internet connection, or files coming down that are particularly large, you can end up waiting a while for the page to complete.
Now you know why you can't host a website from your own computer
If you've read the article you'll know the whole process is pretty complex. The webhosting company must be connected and be able to provide their nameserver info to the DNS (an international lookup system like the phone book) as well as having web server software. Their computers must be on 24-7 and they need added security to prevent hacking and viruses as well as measures to take care of disk failure and connectivity.
That's why you can't just put your website files onto your own computer and expect it to work like its on the internet - unless of course you know what you're doing. Most of us don't - so we pay a Web Hosting company to store the files that make up our website, and we pay them an annual fee for what is a highly technical and complex service.